Commit Graph

143 Commits

Author SHA1 Message Date
Linus Torvalds 8bb1f22952 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull second try at vfs part d#2 from Al Viro:
 "Miklos' first series (with do_lookup() rewrite split into edible
  chunks) + assorted bits and pieces.

  The 'untangling of do_lookup()' series is is a splitup of what used to
  be a monolithic patch from Miklos, so this series is basically "how do
  I convince myself that his patch is correct (or find a hole in it)".
  No holes found and I like the resulting cleanup, so in it went..."

Changes from try 1: Fix a boot problem with selinux, and commit messages
prettied up a bit.

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (24 commits)
  vfs: fix out-of-date dentry_unhash() comment
  vfs: split __lookup_hash
  untangling do_lookup() - take __lookup_hash()-calling case out of line.
  untangling do_lookup() - switch to calling __lookup_hash()
  untangling do_lookup() - merge d_alloc_and_lookup() callers
  untangling do_lookup() - merge failure exits in !dentry case
  untangling do_lookup() - massage !dentry case towards __lookup_hash()
  untangling do_lookup() - get rid of need_reval in !dentry case
  untangling do_lookup() - eliminate a loop.
  untangling do_lookup() - expand the area under ->i_mutex
  untangling do_lookup() - isolate !dentry stuff from the rest of it.
  vfs: move MAY_EXEC check from __lookup_hash()
  vfs: don't revalidate just looked up dentry
  vfs: fix d_need_lookup/d_revalidate order in do_lookup
  ext3: move headers to fs/ext3/
  migrate ext2_fs.h guts to fs/ext2/ext2.h
  new helper: ext2_image_size()
  get rid of pointless includes of ext2_fs.h
  ext2: No longer export ext2_fs.h to user space
  mtdchar: kill persistently held vfsmount
  ...
2012-03-31 13:42:57 -07:00
Al Viro 00292bbf76 mtdchar: kill persistently held vfsmount
... and mtdchar_notifier along with it; just have ->drop_inode() that
will unconditionally get evict them instead of dances on mtd device
removal and use simple_pin_fs() instead of kern_mount()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-03-31 16:03:15 -04:00
Linus Torvalds 623ff7739e MTD merge for 3.4
Artem's cleanup of the MTD API continues apace.
 Fixes and improvements for ST FSMC and SuperH FLCTL NAND, amongst others.
 More work on DiskOnChip G3, new driver for DiskOnChip G4.
 Clean up debug/warning printks in JFFS2 to use pr_<level>.
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Merge tag 'for-linus-3.4' of git://git.infradead.org/mtd-2.6

Pull MTD changes from David Woodhouse:
 - Artem's cleanup of the MTD API continues apace.
 - Fixes and improvements for ST FSMC and SuperH FLCTL NAND, amongst
   others.
 - More work on DiskOnChip G3, new driver for DiskOnChip G4.
 - Clean up debug/warning printks in JFFS2 to use pr_<level>.

Fix up various trivial conflicts, largely due to changes in calling
conventions for things like dmaengine_prep_slave_sg() (new inline
wrapper to hide new parameter, clashing with rewrite of previously last
parameter that used to be an 'append' flag, and is now a bitmap of
'unsigned long flags').

(Also some header file fallout - like so many merges this merge window -
and silly conflicts with sparse fixes)

* tag 'for-linus-3.4' of git://git.infradead.org/mtd-2.6: (120 commits)
  mtd: docg3 add protection against concurrency
  mtd: docg3 refactor cascade floors structure
  mtd: docg3 increase write/erase timeout
  mtd: docg3 fix inbound calculations
  mtd: nand: gpmi: fix function annotations
  mtd: phram: fix section mismatch for phram_setup
  mtd: unify initialization of erase_info->fail_addr
  mtd: support ONFI multi lun NAND
  mtd: sm_ftl: fix typo in major number.
  mtd: add device-tree support to spear_smi
  mtd: spear_smi: Remove default partition information from driver
  mtd: Add device-tree support to fsmc_nand
  mtd: fix section mismatch for doc_probe_device
  mtd: nand/fsmc: Remove sparse warnings and errors
  mtd: nand/fsmc: Add DMA support
  mtd: nand/fsmc: Access the NAND device word by word whenever possible
  mtd: nand/fsmc: Use dev_err to report error scenario
  mtd: nand/fsmc: Use devm routines
  mtd: nand/fsmc: Modify fsmc driver to accept nand timing parameters via platform
  mtd: fsmc_nand: add pm callbacks to support hibernation
  ...
2012-03-30 17:31:56 -07:00
Artem Bityutskiy 3c3c10bba1 mtd: add leading underscore to all mtd functions
This patch renames all MTD functions by adding a "_" prefix:

mtd->erase -> mtd->_erase
mtd->read_oob -> mtd->_read_oob
...

The reason is that we are re-working the MTD API and from now on it is
an error to use MTD function pointers directly - we have a corresponding
API call for every pointer. By adding a leading "_" we achieve the following:

1. Make sure we convert every direct pointer users
2. A leading "_" suggests that this interface is internal and it becomes
   less likely that people will use them directly
3. Make sure all the out-of-tree modules stop compiling and the owners
   spot the big API change and amend them.

Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2012-03-27 00:20:01 +01:00
Muthu Kumar b502bd1152 magic.h: move some FS magic numbers into magic.h
- Move open-coded filesystem magic numbers into magic.h

- Rearrange magic.h so that the filesystem-related constants are grouped
  together.

Signed-off-by: Muthukumar R <muthur@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-23 16:58:31 -07:00
Artem Bityutskiy 800ffd3496 mtd: do not use mtd->block_markbad directly
Instead, use the new 'mtd_can_have_bb()', or just rely on 'mtd_block_markbad()'
return code, which will be -EOPNOTSUPP if bad blocks are not supported.

Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2012-01-09 18:26:26 +00:00
Artem Bityutskiy 8f461a7302 mtd: introduce mtd_can_have_bb helper
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>
2012-01-09 18:26:24 +00:00
Artem Bityutskiy 381345652f mtd: do not use mtd->lock, unlock and is_locked directly
Instead, call the corresponding MTD API function which will return
'-EOPNOTSUPP' if the operation is not supported.

Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2012-01-09 18:26:22 +00:00
Artem Bityutskiy 327cf2922b mtd: do not use mtd->sync directly
This patch teaches 'mtd_sync()' to do nothing when the MTD driver does
not have the '->sync()' method, which allows us to remove all direct
'mtd->sync' accesses.

Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2012-01-09 18:26:21 +00:00
Artem Bityutskiy e2936b2af5 mtd: do not use mtd->lock_user_prot_reg directly
Instead, check the -EOPNOTSUPP return code of 'mtd_lock_user_prot_reg()'.

Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2012-01-09 18:26:18 +00:00
Artem Bityutskiy 27c151a5e5 mtd: mtd->write_user_prot_reg directly
Instead, just call 'mtd_write_user_prot_reg()' and check the '-EOPNOTSUPP' return
code.

Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2012-01-09 18:26:17 +00:00
Artem Bityutskiy b6de3d6cb6 mtd: do not use mtd->read_*_prot_reg directly
Instead, call 'mtd_read_*_prot_info()' and check for -EOPNOTSUPP.

Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2012-01-09 18:26:16 +00:00
Artem Bityutskiy 87e858a97e mtd: do not use mtd->get_*_prot_info directly
Instead, call 'mtd_get_*_prot_info()' and check for '-EOPNOTSUPP'. While
on it, fix the return code from '-EOPNOTSUPP' to '-EINVAL' for the case
when the mode parameter is invalid.

Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2012-01-09 18:26:15 +00:00
Artem Bityutskiy dac2639f98 mtd: do not use mtd->read_oob directly
Instead of checking whether 'mtd->read_oob' is defined, just call
'mtd_read_oob()' and handle the '-EOPNOTSUPP' error which will be returned
if the function is undefined.

Additionally, make 'mtd_write_oob()' return '-EOPNOTSUPP' if the function
is undefined.

Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2012-01-09 18:26:14 +00:00
Artem Bityutskiy cd621274b0 mtd: do not use mtd->get_unmapped_area directly
Remove direct usage of mtd->get_unmapped_area. Instead, just call
'mtd_get_unmapped_area()' which will return -EOPNOTSUPP if the function
is not implemented and test for this error code.

Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2012-01-09 18:26:10 +00:00
Artem Bityutskiy fc002e3c32 mtd: introduce mtd_has_oob helper
We are working in the direction of making sure that MTD clients to not
use 'mtd->func' pointers directly. In some places we want to know if
OOB operations are supported by an MTD device. Introduce 'mtd_has_oob()'
helper for these purposes.

Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2012-01-09 18:26:08 +00:00
Artem Bityutskiy 30fa98480b mtd: remove extra retlen assignment
MTD functions always assign the 'retlen' argument to 0 at the very
beginning - the callers do not have to do this.

I used the following semantic patch to find these places:

@@
identifier retlen;
expression a, b, c, d, e;
constant C;
type T;
@@
(
- retlen = C;
|
T
-retlen = C
+ retlen
;
)

... when != retlen
    when exists

(
mtd_read(a, b, c, &retlen, d)
|
mtd_write(a, b, c, &retlen, d)
|
mtd_panic_write(a, b, c, &retlen, d)
|
mtd_point(a, b, c, &retlen, d, e)
|
mtd_read_fact_prot_reg(a, b, c, &retlen, d)
|
mtd_write_user_prot_reg(a, b, c, &retlen, d)
|
mtd_read_user_prot_reg(a, b, c, &retlen, d)
|
mtd_writev(a, b, c, d, &retlen)
)

I ran it twice, because there were cases of double zero assigments
in mtd tests. Then I went through the patch to verify that spatch
did not find any false positives.

Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2012-01-09 18:25:56 +00:00
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 e95e978645 mtd: introduce mtd_is_locked interface
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2012-01-09 18:25:42 +00:00
Artem Bityutskiy b66005cd3e mtd: introduce mtd_unlock interface
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2012-01-09 18:25:40 +00:00
Artem Bityutskiy 7799f9ac8d mtd: introduce mtd_lock interface
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2012-01-09 18:25:39 +00:00
Artem Bityutskiy 85f2f2a809 mtd: introduce mtd_sync interface
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2012-01-09 18:25:35 +00:00
Artem Bityutskiy 4403dbfb45 mtd: introduce mtd_lock_user_prot_reg interface
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2012-01-09 18:25:33 +00:00
Artem Bityutskiy 482b43adbb mtd: introduce mtd_write_user_prot_reg interface
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2012-01-09 18:25:31 +00:00
Artem Bityutskiy 4ea1cabb92 mtd: introduce mtd_read_user_prot_reg interface
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2012-01-09 18:25:30 +00:00
Artem Bityutskiy 855e5d8cfe mtd: introduce mtd_get_user_prot_info interface
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2012-01-09 18:25:29 +00:00
Artem Bityutskiy d264f72ae5 mtd: introduce mtd_read_fact_prot_reg interface
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2012-01-09 18:25:27 +00:00
Artem Bityutskiy a750b5ce5e mtd: introduce mtd_get_fact_prot_info interface
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2012-01-09 18:25:25 +00:00
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 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 04c601bfa4 mtd: introduce mtd_get_unmapped_area interface
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2012-01-09 18:25:18 +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
Artem Bityutskiy 969e57adc2 mtd: mtdchar: rename functions
We are going to re-work the MTD interface and change 'mtd->write()' to
'mtd_write()', 'mtd->read()' to 'mtd_read()' and so forth for all functions
in the 'struct mtd_info' structure.

However, mtdchar.c has its own 'mtd_read()', 'mtd_write()', etc functions
which collide with our changes. This patch renames these functions
to 'mtdchar_read()', 'mtdchar_write()', etc.

Additionally, to make the 'mtdchar.c' file look consistent, rename
similarly all the other functions starting with 'mtd_'.

Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2012-01-09 18:25:02 +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
Miklos Szeredi 6d6b77f163 filesystems: add missing nlink wrappers
Replace direct i_nlink updates with the respective updater function
(inc_nlink, drop_nlink, clear_nlink, inode_dec_link_count).

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2011-11-02 12:53:43 +01:00
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 19fb4341ad mtd: kill old field for `struct mtd_info_user'
The ecctype and eccsize fields have been obsolete for a while. Since they
don't have any users, we can kill them and leave padding in their place
for now.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@intel.com>
2011-09-11 15:57:44 +03:00
Brian Norris e99d8b089a mtd: add MEMWRITE ioctl
Implement a new ioctl for writing both page data and OOB to flash at the
same time. This ioctl is intended to be a generic interface that can
replace other ioctls (MEMWRITEOOB and MEMWRITEOOB64) and cover the
functionality of several other old ones, e.g., MEMWRITE can:

* write autoplaced OOB instead of using ECCGETLAYOUT (deprecated) and
  working around the reserved areas
* write raw (no ECC) OOB instead of using MTDFILEMODE to set the
  per-file-descriptor MTD_FILE_MODE_RAW
* write raw (no ECC) data instead of using MTDFILEMODE
  (MTD_FILE_MODE_RAW) and using standard character device "write"

This ioctl is especially useful for MLC NAND, which cannot be written
twice (i.e., we cannot successfully write the page data and OOB in two
separate operations). Instead, MEMWRITE can write both in a single
operation.

Note that this ioctl is not affected by the MTD file mode (i.e.,
MTD_FILE_MODE_RAW vs. MTD_FILE_MODE_NORMAL), since it receives its write
mode as an input parameter.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@intel.com>
2011-09-11 15:56:25 +03:00
Brian Norris beb133fc16 mtd: rename MTD_MODE_* to MTD_FILE_MODE_*
These modes hold their state only for the life of their file descriptor,
and they overlap functionality with the MTD_OPS_* modes. Particularly,
MTD_MODE_RAW and MTD_OPS_RAW cover the same function: to provide raw
(i.e., without ECC) access to the flash. In fact, although it may not be
clear, MTD_MODE_RAW implied that operations should enable the
MTD_OPS_RAW mode.

Thus, we should be specific on what each mode means. This is a start,
where MTD_FILE_MODE_* actually represents a "file mode," not necessarily
a true global MTD mode.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@intel.com>
2011-09-11 15:29:36 +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 c46f6483d2 mtd: support reading OOB without ECC
This fixes issues with `nanddump -n' and the MEMREADOOB[64] ioctls on
hardware that performs error correction when reading only OOB data. A
driver for such hardware needs to know when we're doing a RAW vs. a
normal write, but mtd_do_read_oob does not pass such information to the
lower layers (e.g., NAND). We should pass MTD_OOB_RAW or MTD_OOB_PLACE
based on the MTD file mode.

For now, most drivers can get away with just setting:

  chip->ecc.read_oob_raw = chip->ecc.read_oob

This is done by default; but for systems that behave as described above,
you must supply your own replacement function.

This was tested with nandsim as well as on actual SLC NAND.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Cc: Jim Quinlan <jim2101024@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@intel.com>
2011-09-11 15:13:38 +03:00
Brian Norris 9ce244b3fb mtd: support writing OOB without ECC
This fixes issues with `nandwrite -n -o' and the MEMWRITEOOB[64] ioctls
on hardware that writes ECC when writing OOB. The problem arises as
follows: `nandwrite -n' can write page data to flash without applying
ECC, but when used with the `-o' option, ECC is applied (incorrectly),
contrary to the `--noecc' option.

I found that this is the case because my hardware computes and writes
ECC data to flash upon either OOB write or page write. Thus, to support
a proper "no ECC" write, my driver must know when we're performing a raw
OOB write vs. a normal ECC OOB write. However, MTD does not pass any raw
mode information to the write_oob functions.  This patch addresses the
problems by:

1) Passing MTD_OOB_RAW down to lower layers, instead of just defaulting
   to MTD_OOB_PLACE
2) Handling MTD_OOB_RAW within the NAND layer's `nand_do_write_oob'
3) Adding a new (replaceable) function pointer in struct ecc_ctrl; this
   function should support writing OOB without ECC data. Current
   hardware often can use the same OOB write function when writing
   either with or without ECC

This was tested with nandsim as well as on actual SLC NAND.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Cc: Jim Quinlan <jim2101024@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@intel.com>
2011-09-11 15:02:18 +03:00
Brian Norris 305b93f180 mtd: do not assume oobsize is power of 2
Previous generations of MTDs all used OOB sizes that were powers of 2,
(e.g., 64, 128). However, newer generations of flash, especially NAND,
use irregular OOB sizes that are not powers of 2 (e.g., 218, 224, 448).
This means we cannot use masks like "mtd->oobsize - 1" to assume that we
will get a proper bitmask for OOB operations.

These masks are really only intended to hide the "page" portion of the
offset, leaving any OOB offset intact, so a masking with the writesize
(which *is* always a power of 2) is valid and makes more sense.

This has been tested for read/write of NAND devices (nanddump/nandwrite)
using nandsim and actual NAND flash.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@intel.com>
2011-09-11 15:02:17 +03:00
Brian Norris 92394b5c2b mtd: spelling fixes
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
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
Brian Norris c478d7e449 mtd: edit NAND-related comment
This comment was unclear regarding which NAND functions do and do not
support ECC on the spare area. This update should reflect the current
status of the NAND system but can be updated if changes are made in
the standard functions.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Artem Bityutskiy <dedekind1@gmail.com>
2011-09-11 15:02:14 +03:00
Brian Norris 041e4575f0 mtd: nand: handle ECC errors in OOB
While the standard NAND OOB functions do not do ECC on the spare area,
it is possible for a driver to supply its own OOB ECC functions (e.g., HW
ECC). nand_do_read_oob should act like nand_do_read_ops in checking the
ECC stats and returning -EBADMSG or -EUCLEAN on uncorrectable errors or
correctable bitflips, respectively. These error codes could be used in
flash-based BBT code or in YAFFS, for example.

Doing this, however, messes with the behavior of mtd_do_readoob. Now,
mtd_do_readoob should check whether we had -EUCLEAN or -EBADMSG errors
and discard those as "non-fatal" so that the ioctls can still succeed
with (possibly uncorrected) data.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2011-09-11 15:02:14 +03:00