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: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

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: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

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: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

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: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

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: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

Replace direct i_nlink updates with the respective updater function
(inc_nlink, drop_nlink, clear_nlink, inode_dec_link_count).
Signed-off-by: NMiklos Szeredi <mszeredi@suse.cz>

Signed-off-by: NBrian Norris <computersforpeace@gmail.com>
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@intel.com>

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: NBrian Norris <computersforpeace@gmail.com>
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@intel.com>

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: NBrian Norris <computersforpeace@gmail.com>
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@intel.com>

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: NBrian Norris <computersforpeace@gmail.com>
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@intel.com>

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: NBrian Norris <computersforpeace@gmail.com>
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@intel.com>

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: NBrian Norris <computersforpeace@gmail.com>
Cc: Jim Quinlan <jim2101024@gmail.com>
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@intel.com>

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: NBrian Norris <computersforpeace@gmail.com>
Cc: Jim Quinlan <jim2101024@gmail.com>
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@intel.com>

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: NBrian Norris <computersforpeace@gmail.com>
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@intel.com>

Signed-off-by: NBrian Norris <computersforpeace@gmail.com>
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@intel.com>

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: NBrian Norris <computersforpeace@gmail.com>
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@intel.com>

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: NBrian Norris <computersforpeace@gmail.com>
Signed-off-by: NArtem Bityutskiy <dedekind1@gmail.com>

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: NBrian Norris <computersforpeace@gmail.com>
Signed-off-by: NArtem Bityutskiy <Artem.Bityutskiy@nokia.com>

Therefor -> Therefore
[Intern], [Internal] -> [INTERN]
[REPLACABLE] -> [REPLACEABLE]
syndrom, syndom -> syndrome
ecc -> ECC
buswith -> buswidth
endianess -> endianness
dont -> don't
occures -> occurs
independend -> independent
wihin -> within
erease -> erase
blockes -> blocks
...
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>
Signed-off-by: NArtem Bityutskiy <Artem.Bityutskiy@nokia.com>

On writes in MODE_RAW the mtd_oob_ops struct is not sufficiently
initialized which may cause nandwrite to fail. With this patch
it is possible to write raw nand/oob data without additional ECC
(either for testing or when some sectors need different oob layout
e.g. bootloader) like
nandwrite  -n -r -o  /dev/mtd0 <myfile>
Signed-off-by: NPeter Wippich <pewi@gw-instruments.de>
Cc: stable@kernel.org
Tested-by: NRicard Wanderlof <ricardw@axis.com>
Signed-off-by: NArtem Bityutskiy <Artem.Bityutskiy@nokia.com>

For a number of file systems that don't have a mount point (e.g. sockfs
and pipefs), they are not marked as long term. Therefore in
mntput_no_expire, all locks in vfs_mount lock are taken instead of just
local cpu's lock to aggregate reference counts when we release
reference to file objects.  In fact, only local lock need to have been
taken to update ref counts as these file systems are in no danger of
going away until we are ready to unregister them.

The attached patch marks file systems using kern_mount without
mount point as long term.  The contentions of vfs_mount lock
is now eliminated.  Before un-registering such file system,
kern_unmount should be called to remove the long term flag and
make the mount point ready to be freed.
Signed-off-by: NTim Chen <tim.c.chen@linux.intel.com>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Now that none of the drivers use CONFIG_MTD_PARTITIONS we can remove
it from Kconfig and the last remaining uses.
Signed-off-by: NJamie Iles <jamie@jamieiles.com>
Signed-off-by: NArtem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

Replace direct call to kmalloc for a potentially large, contiguous
buffer allocation with one to mtd_kmalloc_up_to which helps ensure the
operation can succeed under low-memory, highly- fragmented situations
albeit somewhat more slowly.
Signed-off-by: NGrant Erickson <marathon96@gmail.com>
Tested-by: NBen Gardiner <bengardiner@nanometrics.ca>
Tested-by: NStefano Babic <sbabic@denx.de>
Signed-off-by: NArtem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>