Commit Graph

96 Commits

Author SHA1 Message Date
Sheng Yong 192db1caa2 mtd: nand_bbt: set the smallest size of bbt table
When using nandsim to simulate a 128K block nand with `overridesize = 1',
the size of mtd device is too small (mtd_size = 4 * block_size) to get the
right length of bbt. Then when creating bbt, kzmalloc() will return
ZERO_SIZE_PTR. This causes a NULL pointer oops when scanning bbt.

[  952.156166] BUG: unable to handle kernel NULL pointer dereference at 0000000000000010
[  952.157064] IP: [<ffffffff8148ad4a>] nand_isreserved_bbt+0x2a/0x40
[  952.157064] PGD 0
[  952.157064] Oops: 0000 [#1] SMP
[  952.157064] Modules linked in: nandsim(+) [last unloaded: nandsim]
[  952.157064] CPU: 1 PID: 7103 Comm: modprobe Not tainted 4.2.0-rc3-next-20150724 #4
[  952.157064] Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS VirtualBox 12/01/2006
[  952.157064] task: ffff88003e24b980 ti: ffff88003d274000 task.ti: ffff88003d274000
[  952.157064] RIP: 0010:[<ffffffff8148ad4a>]  [<ffffffff8148ad4a>] nand_isreserved_bbt+0x2a/0x40
[  952.157064] RSP: 0018:ffff88003d277b90  EFLAGS: 00010246
[  952.157064] RAX: 0000000000000010 RBX: ffff88003d5a1000 RCX: 0000000000000000
[  952.157064] RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff88003d919000
[  952.157064] RBP: ffff88003d277b98 R08: 0000000000020000 R09: 0000000000000000
[  952.157064] R10: 0000000000000000 R11: 0000000000000195 R12: ffff88003d919000
[  952.157064] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
[  952.157064] FS:  00007fada4d07700(0000) GS:ffff88003fd00000(0000) knlGS:0000000000000000
[  952.157064] CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
[  952.157064] CR2: 0000000000000010 CR3: 0000000037924000 CR4: 00000000000006a0
[  952.157064] Stack:
[  952.157064]  ffffffff814851ec ffff88003d277ba8 ffffffff8147e35f ffff88003d277bf8
[  952.157064]  ffffffff814816f3 ffff88003d277c08 ffff88003d277bc8 0000000000000282
[  952.157064]  0000000000000001 0000000000000000 ffff88003d209540 0000000000000001
[  952.157064] Call Trace:
[  952.157064]  [<ffffffff814851ec>] ? nand_block_isreserved+0x1c/0x20
[  952.157064]  [<ffffffff8147e35f>] mtd_block_isreserved+0x1f/0x30
[  952.157064]  [<ffffffff814816f3>] allocate_partition+0x463/0x6a0
[  952.157064]  [<ffffffff81481b3b>] add_mtd_partitions+0x4b/0xe0
[  952.157064]  [<ffffffff8147f14c>] mtd_device_parse_register+0x4c/0xe0
[  952.157064]  [<ffffffffa0013daf>] ns_init_module+0xdaf/0xde4 [nandsim]
[  952.157064]  [<ffffffff8128d7c8>] ? kasprintf+0x38/0x40
[  952.157064]  [<ffffffffa0013000>] ? 0xffffffffa0013000
[  952.157064]  [<ffffffff810002c3>] do_one_initcall+0x83/0x1b0
[  952.157064]  [<ffffffff8113afab>] ? kmem_cache_alloc_trace+0x6b/0x120
[  952.157064]  [<ffffffff8160b503>] do_init_module+0x5c/0x1dd
[  952.157064]  [<ffffffff810aa4db>] load_module+0x1bbb/0x20b0
[  952.157064]  [<ffffffff810a6fc0>] ? __symbol_put+0x30/0x30
[  952.157064]  [<ffffffff810aaac9>] SyS_init_module+0xf9/0x110
[  952.157064]  [<ffffffff810aa9d1>] ? SyS_init_module+0x1/0x110
[  952.157064]  [<ffffffff81615f57>] entry_SYSCALL_64_fastpath+0x12/0x6a
[  952.157064] Code: 00 55 48 8b 87 80 01 00 00 48 89 e5 8b 88 cc 00 00 00 48 8b 80 f0 03 00 00 5d 48 d3 fe 89 f2 83 e6 03 c1 fa 02 8d 0c 36 48 63 d2 <0f> b6 04 10 d3 f8 83 e0 03 3c 02 0f 94 c0 0f b6 c0 c3 0f 1f 40
[  952.157064] RIP  [<ffffffff8148ad4a>] nand_isreserved_bbt+0x2a/0x40
[  952.157064]  RSP <ffff88003d277b90>
[  952.157064] CR2: 0000000000000010
[  952.204010] ---[ end trace 6ca2e1c041fdba36 ]---

This patch gives a smallest length to bbt, 1 byte, which is enough to
represent up to 4 blocks.

Signed-off-by: Sheng Yong <shengyong1@huawei.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2015-10-11 12:58:28 -07:00
Brian Norris b74bdbe588 mtd: remove incorrect file name
This is an example of why it doesn't make much sense to put this
information here in the first place. I don't really know what purpose it
serves.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2015-05-22 10:57:46 -07:00
Brian Norris f5cd2ae1e4 mtd: nand_bbt: fix theoretical integer overflow in BBT write
This statement was written with a cast-to-loff_t to be sure to have a
full 64-bit mask. However, we don't account for the fact that
'1 << this->bbt_erase_shift' might already overflow.

This will not be a problem in practice, since eraseblocks should never
be anywhere near 4GiB. But we can do this for completeness, and quiet
Coverity in the meantime. CID #1226806.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2015-05-06 20:02:37 -07:00
Brian Norris 83c59542d0 mtd: nand_bbt: unify/fix error handling in nand_scan_bbt()
Don't leak this->bbt, and return early if check_create() fails. It helps
to have a single error path to avoid these problems.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2015-05-06 20:02:36 -07:00
Brian Norris 17799359e7 mtd: nand_bbt: make nand_scan_bbt() static
This implementation detail is no longer needed outside of nand_bbt.c.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2015-05-06 20:02:35 -07:00
Brian Norris a2281e821f mtd: nand_bbt: drop unnecessary header
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2015-05-06 20:02:33 -07:00
Rafał Miłecki 2ac63d901b mtd: nand: don't break long print messages
This follows Chapter 2 of Linux's CodingStyle:
> However, never break user-visible strings such as printk messages,
> because that breaks the ability to grep for them.

Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2014-09-17 23:29:36 -07:00
Ezequiel Garcia 8471bb73ba mtd: Introduce mtd_block_isreserved()
In addition to mtd_block_isbad(), which checks if a block is bad or
reserved, it's needed to check if a block is reserved only (but not
bad). This commit adds an MTD interface for it, in a similar fashion to
mtd_block_isbad().

While here, fix mtd_block_isbad() so the out-of-bounds checking is done
before the callback check.

Signed-off-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Tested-by: Pekon Gupta <pekon@ti.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2014-07-08 18:38:16 -07:00
Brian Norris abb9cf78e8 mtd: nand_bbt: handle error case for nand_create_badblock_pattern()
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2014-05-28 00:05:25 -07:00
Brian Norris 930de53701 mtd: nand_bbt: remove unused variable
Set, but unused, variable.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2014-05-28 00:05:25 -07:00
Brian Norris 5961ad2cb4 mtd: nand_bbt: kill NAND_BBT_SCANALLPAGES
Now that the last user of NAND_BBT_SCANALLPAGES has been removed, let's
kill this peculiar BBT feature flag.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Reviewed-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
2013-11-06 23:33:14 -08:00
Brian Norris 552fb55d6e mtd: nand: stop exporting nand_default_bbt
I removed the last non-nand_base users of this, and we shouldn't have
any more modules that need to access it. It's only non-static to share
between nand_base and nand_bbt.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2013-10-27 16:26:59 -07:00
Brian Norris dad2256269 mtd: nand: remove NAND_BBT_SCANEMPTY
NAND_BBT_SCANEMPTY is a strange, badly-supported option with omap as its
single remaining user.

NAND_BBT_SCANEMPTY was likely used by accident in omap2[1]. And anyway,
omap2 doesn't scan the chip for bad blocks (courtesy of
NAND_SKIP_BBTSCAN), and so its use of this option is irrelevant.

This patch drops the NAND_BBT_SCANEMPTY option.

[1] http://lists.infradead.org/pipermail/linux-mtd/2012-July/042902.html

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Cc: Ivan Djelic <ivan.djelic@parrot.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2013-08-30 16:48:37 +01:00
Brian Norris b32843b772 mtd: nand: hide in-memory BBT implementation details
nand_base.c shouldn't have to know the implementation details of
nand_bbt's in-memory BBT. Specifically, nand_base shouldn't perform the
bit masking and shifting to isolate a BBT entry.

Instead, just move some of the BBT code into a new nand_markbad_bbt()
interface. This interface allows external users (i.e., nand_base) to
mark a single block as bad in the BBT. Then nand_bbt will take care of
modifying the in-memory BBT and updating the flash-based BBT (if
applicable).

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2013-08-30 16:48:17 +01:00
Brian Norris 5a0edb251a mtd: nand: refactor chip->block_markbad interface
The chip->block_markbad pointer should really only be responsible for
writing a bad block marker for new bad blocks. It should not take care
of BBT-related functionality, nor should it handle bookkeeping of bad
block stats.

This patch refactors the 3 users of the block_markbad interface (plus
the default nand_base implementation) so that the common code is kept in
nand_block_markbad_lowlevel(). It removes some inconsistencies between
the various implementations and should allow for more centralized
improvements in the future.

Because gpmi-nand no longer needs the nand_update_bbt() function, let's
stop exporting it as well.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Acked-by: Huang Shijie <b32955@freescale.com> (for gpmi-nand parts)
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2013-08-30 16:47:52 +01:00
Brian Norris 39dbb02998 mtd: nand: eliminate cast
Just make 'res' an int.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2013-08-30 16:44:49 +01:00
Brian Norris b4d20d601f mtd: nand: remove multiplied-by-2 block logic
The parent commit 771c568bcf ("mtd: nand: add
accessors, macros for in-memory BBT") makes the following comment obsolete:

	/*
	 * Note that numblocks is 2 * (real numblocks) here, see i+=2
	 * below as it makes shifting and masking less painful
	 */

I don't think it ever could have been "less painful" to have to shift an
extra bit (or 2, or 3) at various points in nand_bbt.c (and even
outside, since we leak our in-memory format). But now it is certainly
more painful, since we have nice macros and functions to retrieve the
relevant portions of the BBT.

This patch removes any points where the block number is
doubled/halved/otherwise-shifted, instead representing the block number
in its most natural form: as the actual block number.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2013-08-30 16:43:44 +01:00
Brian Norris 771c568bcf mtd: nand: add accessors, macros for in-memory BBT
There is an abundance of magic numbers and complicated shifting/masking
logic in the in-memory BBT code which makes the code unnecessary complex
and hard to read.

This patch adds macros to represent the 00b, 01b, 10b, and 11b
memory-BBT magic numbers, as well as two accessor functions for reading
and marking the memory-BBT bitfield for a given block.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2013-08-30 16:42:48 +01:00
Artem Bityutskiy 14c6578683 mtd: nand: remove AG-AND support
We have only one AG-AND driver and it was not touched since 2005. It looks
like AG-AND was not really make it to mass-production and can be considered
a dead technology.

Along with the AG-AND support, this patch removes the BBT_AUTO_REFRESH feature,
because the only user of this feature is AG-AND. And even though it is
implemented as a generic feature, I prefer to remove it because NAND flashes do
not really need it in this form.

Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Acked-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2013-04-05 12:00:50 +01:00
Richard Genoud 61de9da657 mtd: nand: use NAND_BBT_SCAN_MAXBLOCKS
In nand_bbt.c, a hardcoded value was used instead of the define meant
for that, so we use the define.

There's no functional change.

Signed-off-by: Richard Genoud <richard.genoud@gmail.com>
Acked-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2012-09-29 15:54:10 +01:00
Fabio Estevam d159c4e5fb mtd: nand: nand_bbt: export nand_update_bbt
When building MTD_NAND_GPMI_NAND as module, the following error shows up:

ERROR: "nand_update_bbt" [drivers/mtd/nand/gpmi-nand/gpmi_nand.ko] undefined!

Export nand_update_bbt to fix it.

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2012-09-29 15:11:27 +01:00
Shmulik Ladkani eceb84b188 mtd: nand: rename create_bbt()'s 'len' variable to 'numpages'
Rename 'len' variable of create_bbt/scan_block_fast/scan_block_full to
'numpages', since it really means number of pages to scan when
searching for the BBM (and not the byte length of the scan).

Signed-off-by: Shmulik Ladkani <shmulik.ladkani@gmail.com>
Reviewed-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2012-09-29 15:10:37 +01:00
Brian Norris af69dcd386 mtd: nand: rename '_raw' BBT scan functions
None of these scanning functions use MTD_OPS_RAW mode any more, so there's
really nothing 'raw' about them. Rename them to (hopefully) make the code
a little clearer.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2012-09-29 14:52:04 +01:00
Brian Norris a7e68834fc mtd: nand: use ECC, if present, when scanning OOB
scan_read_raw_oob() is used in only in places where the MTD_OPS_PLACE_OOB mode
is preferable to MTD_OPS_RAW mode, so use MTD_OPS_PLACE_OOB instead.
MTD_OPS_PLACE_OOB provides the same functionality with the potential[1] added
bonus of error correction.

This brings scan_block_full() in line with scan_block_fast() so that they
both read bad block markers with MTD_OPS_PLACE_OOB. This can help in
preventing 0xff markers (in good blocks) from being interpreted as bad
block indicators in the presence of a single bitflip.

Note that ECC error codes (EUCLEAN or EBADMSG) are already silently
ignored in all users of scan_read_raw_oob().

[1] Few  drivers perform proper error correction on OOB data. In those
    cases, the use of MTD_OPS_RAW vs. MTD_OPS_PLACE_OOB is not
    significant.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2012-09-29 14:51:55 +01:00
Brian Norris 491ed06f33 mtd: nand_bbt: use string library
Some nand_bbt code can be shortened by using memcmp() and memchr_inv().
As an added bonus, there is a possible performance benefit.

Borrowed some code from Akinobu Mita.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2012-09-29 14:51:13 +01:00
Brian Norris 7b5a2d4097 mtd: nand: remove unused 'int' return codes
The return codes for read_abs_bbts() and search_read_bbts() are always
non-zero, and so don't have much meaning. Just remove them.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Reviewed-by: Shmulik Ladkani <shmulik.ladkani@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2012-09-29 14:51:00 +01:00
Huang Shijie 44ed0ffdbc mtd: fix typo in comment
fix the comment for nand_bbt.c

Signed-off-by: Huang Shijie <b32955@freescale.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2012-07-16 21:45:05 +01:00
Brian Norris 718894ad94 mtd: nand_bbt: refactor check_pattern_no_oob()
This function only returns 0 or -1, so make that clear.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2012-07-06 18:17:08 +01:00
Brian Norris 9fd6b37a08 mtd: nand: rename "no_bbt" descriptors to "no_oob"
These descriptors are for BBT's that don't use OOB; the "no_bbt" name doesn't
really make sense.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2012-07-06 18:17:08 +01:00
Shmulik Ladkani 7bb9c75436 mtd: nand: Use the mirror BBT descriptor when reading its version
The code responsible for reading the version of the mirror bbt was
incorrectly using the descriptor of the main bbt.

Pass the mirror bbt descriptor to 'scan_read_raw' when reading the
version of the mirror bbt.

Signed-off-by: Shmulik Ladkani <shmulik.ladkani@gmail.com>
Acked-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: stable@vger.kernel.org [v2.6.37+]
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2012-07-06 18:17:06 +01:00
Dmitry Maluka 34a5704d91 mtd: nand: fix scan_read_raw_oob
It seems there is a bug in scan_read_raw_oob() in nand_bbt.c which
should cause wrong functioning of NAND_BBT_SCANALLPAGES option.

Artem: the patch did not apply and I had to amend it a bit.

Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Cc: stable@kernel.org
2012-05-29 11:14:58 +03:00
Artem Bityutskiy a2cc5ba075 mtd: introduce mtd_write_oob interface
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2012-01-09 18:25:24 +00:00
Artem Bityutskiy fd2819bbc9 mtd: introduce mtd_read_oob interface
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2012-01-09 18:25:23 +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
Linus Torvalds e0d65113a7 Merge git://git.infradead.org/mtd-2.6
* git://git.infradead.org/mtd-2.6: (226 commits)
  mtd: tests: annotate as DANGEROUS in Kconfig
  mtd: tests: don't use mtd0 as a default
  mtd: clean up usage of MTD_DOCPROBE_ADDRESS
  jffs2: add compr=lzo and compr=zlib options
  jffs2: implement mount option parsing and compression overriding
  mtd: nand: initialize ops.mode
  mtd: provide an alias for the redboot module name
  mtd: m25p80: don't probe device which has status of 'disabled'
  mtd: nand_h1900 never worked
  mtd: Add DiskOnChip G3 support
  mtd: m25p80: add EON flash EN25Q32B into spi flash id table
  mtd: mark block device queue as non-rotational
  mtd: r852: make r852_pm_ops static
  mtd: m25p80: add support for at25df321a spi data flash
  mtd: mxc_nand: preset_v1_v2: unlock all NAND flash blocks
  mtd: nand: switch `check_pattern()' to standard `memcmp()'
  mtd: nand: invalidate cache on unaligned reads
  mtd: nand: do not scan bad blocks with NAND_BBT_NO_OOB set
  mtd: nand: wait to set BBT version
  mtd: nand: scrub BBT on ECC errors
  ...

Fix up trivial conflicts:
 - arch/arm/mach-at91/board-usb-a9260.c
	Merged into board-usb-a926x.c
 - drivers/mtd/maps/lantiq-flash.c
	add_mtd_partitions -> mtd_device_register vs changed to use
	mtd_device_parse_register.
2011-11-07 09:11:16 -08:00
Paul Gortmaker f3bcc0179a mtd: Add export.h for EXPORT_SYMBOL/THIS_MODULE where needed
These two common macros will be no longer present everywhere.
Call out the include needs of them explicitly where required.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-10-31 19:31:11 -04:00
Brian Norris 75b66d8ccd mtd: nand: switch `check_pattern()' to standard `memcmp()'
A portion of the `check_pattern()' function is basically a `memcmp()'.
Since it's possible for `memcmp()' to be optimized for a particular
architecture, we should use it instead.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@intel.com>
2011-09-21 09:19:08 +03:00
Brian Norris 752ed6c5f8 mtd: nand: do not scan bad blocks with NAND_BBT_NO_OOB set
Updates to our default function for creating bad block patterns have
broken the "no OOB" feature. The NAND_BBT_NO_OOB option should not be
set while scanning for bad blocks, but we've been passing all BBT
options from nand_chip.bbt_options to the bad block scan. This causes us
to hit the:

	BUG_ON(bd->options & NAND_BBT_NO_OOB);

in create_bbt() when we scan the flash for bad blocks.

Thus, while it can be legal to set NAND_BBT_NO_OOB in a custom badblock
pattern descriptor (presumably with NAND_BBT_CREATE disabled?), we
should not pass it through in our default function.

Also, to help clarify and emphasize that the function creates bad block
patterns only (not, for example, table descriptors for locating
flash-based BBT), I renamed `nand_create_default_bbt_descr' to
`nand_create_badblock_pattern'.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@intel.com>
2011-09-21 09:19:08 +03:00
Brian Norris dadc17a3e3 mtd: nand: wait to set BBT version
Because there are so many cases of checking, writing, and re-writing of
the bad block table(s), we might as well wait until the we've settled on
a valid, clean copy of the table. This also prevents us from falsely
incrementing the table version. For example, we may have the following:

  Primary table, with version 0x02
  Mirror table, with version 0x01
  Primary table has uncorrectable ECC errors

If we don't have this fix applied, then we will:

  Choose to read the primary table (higher version)
  Set mirror table version to 0x02
  Read back primary table
  Invalidate table because of ECC errors
  Retry readback operation with mirror table, now version 0x02
  Mirrored table reads cleanly
  Writeback BBT to primary table location (with "version 0x02")

However, the mirrored table shouldn't have a new version number.
Instead, we actually want:

  Choose to read the primary table (higher version)
  Read back primary table
  Invalidate table because of ECC errors
  Retry readback with mirror table (version 0x01)
  Mirrored table reads cleanly
  Set both tables to version 0x01
  Writeback BBT to primary table location (version 0x01)

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@intel.com>
2011-09-21 09:19:08 +03:00
Brian Norris 623978de36 mtd: nand: scrub BBT on ECC errors
Now that `read_bbt()' returns ECC error codes properly, we handle those
codes when checking the integrity of our flash-based BBT.

The modifications can be described by this new policy:

*) On any uncorrected ECC error, we invalidate the corresponding table
   and retry our version-checking integrity logic.
*) On corrected bitflips, we mark both tables for re-writing to flash
   (a.k.a. scrubbing).

Current integrity checks (i.e., comparing version numbers, etc.) should
take care of all the cases that result in rescanning the device for bad
blocks or falling back to the BBT as found in the mirror descriptor.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@intel.com>
2011-09-21 09:19:07 +03:00
Brian Norris 167a8d5250 mtd: nand: report ECC errors properly when reading BBT
Instead of just printing a warning when encountering ECC errors, we
should return a proper error status and print a more informative
warning. Later, we will handle these error messages in the upper layers
of the BBT scan.

Note that this patch makes our check for ECC error codes a little bit
more restrictive, leaving all unrecognized errors to the generic "else"
clause. This shouldn't cause problems and could even be a benefit.

This code is based on some findings reported by Matthieu Castet.

Reported-by: Matthieu CASTET <matthieu.castet@parrot.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@intel.com>
2011-09-21 09:19:07 +03:00
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
Brian Norris b61bf5bbf6 mtd: nand: remove gotos in `check_create()'
This is a second step in restructuring `check_create()'. When we don't
rely on goto statements for our main functionality, the code will become
a little easier to manipulate.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@intel.com>
2011-09-11 17:16:03 +03:00
Brian Norris c5e8ef9c21 mtd: nand: begin restructuring check_create
We will begin restructuring the code for check_create so that we can
make some important changes. For now, we should just begin to get rid of
some goto statements to make things cleaner. This is the first step of a
few, which are separated to make them easier to follow.

This step should just be a code refactor.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@intel.com>
2011-09-11 17:15:56 +03:00
Brian Norris 596d74527a mtd: nand: fix style
Remove some extra spaces
Consistently use '0x' prefix for bitfield-like constants
Spelling: "aplies" -> "applies"

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@intel.com>
2011-09-11 16:59:58 +03:00
Brian Norris 1196ac5a99 mtd: nand: remove unnecessary variable
`writeops' is unnecessary in the function `nand_update_bbt()'

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@intel.com>
2011-09-11 16:57:49 +03:00
Brian Norris afa17de262 mtd: nand: do not ignore all ECC errors
There are a few reasons not to ignore ECC errors here.

First, mtd->read_oob is being called in raw mode, so there should be no
error correction in the first place.

Second, if we change this such that there *is* error correction in this
function, then we will want to pass the error message upward.

In fact, the code I introduced to "ignore ECC errors" would have been
better if it had just placed this test down in `scan_block_full()' in
the first place. We would like to ignore ECC errors when we are simply
checking for bad block markers (e.g., factory marked), but we may not
want to ignore ECC errors when scanning OOB for a flash-based BBT
pattern (in `scan_read_raw()'; note that the return codes from
`scan_read_raw()' are not actually handled yet).

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@intel.com>
2011-09-11 16:48:49 +03:00
Brian Norris 105513cc4a mtd: nand: refactor scanning code
A few pieces of code are unnecessarily duplicated. For easier
maintenance, we should fix this.

This should have no functional effect.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@intel.com>
2011-09-11 16:48:47 +03:00
Brian Norris 0612b9ddc2 mtd: rename MTD_OOB_* to MTD_OPS_*
These modes are not necessarily for OOB only. Particularly, MTD_OOB_RAW
affected operations on in-band page data as well. To clarify these
options and to emphasize that their effect is applied per-operation, we
change the primary prefix to MTD_OPS_.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@intel.com>
2011-09-11 15:28:59 +03:00
Brian Norris 289c052221 mtd: replace DEBUG() with pr_debug()
Start moving away from the MTD_DEBUG_LEVEL messages. The dynamic
debugging feature is a generic kernel feature that provides more
flexibility.

(See Documentation/dynamic-debug-howto.txt)

Also fix some punctuation, indentation, and capitalization that went
along with the affected lines.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@intel.com>
2011-09-11 15:02:16 +03:00