linux-toradex.git/drivers/mtd/mtdcore.c, branch v4.10

mtd: Allocate bdi objects dynamically

2016-12-01T18:03:17+00:00

The MTD backing dev info objects mtd_bdi was statically allocated.
So when MTD is built as a loadable module, this object fall in the
vmalloc address space.

The problem with that, is that the BDI APIs use wake_up_bit(), which calls
virt_to_page() to retrieve the memory zone of the page containing the
wait_queue to wake up, and virt_to_page() is not valid for vmalloc or
highmem addresses.

Fix this by allocating the BDI objects dynamically with kmalloc. The
objects now fall in the logical address space so that BDI APIs will
work in all cases (mtd builtin or module).

Signed-off-by: Steve Longerbeam 
Signed-off-by: Jim Baxter 
Signed-off-by: Sandeep Jain 
Reviewed-by: Richard Weinberger 
Reviewed-by: Marek Vasut 
Signed-off-by: Brian Norris

mtd: remove unneeded initializer in mtd_ooblayout_count_bytes()

2016-11-19T18:31:34+00:00

There is no need to initialize oobregion since it will be filled by
the iterator.

This function is called with mtd_ooblayout_free or mtd_ooblayout_ecc
for the iterator; both of them calls memset() to clear the oobregion.

Signed-off-by: Masahiro Yamada 
Reviewed-by: Marek Vasut 
Signed-off-by: Boris Brezillon

mtd: use min_t() to refactor mtd_ooblayout_{get, set}_bytes()

2016-11-19T18:31:32+00:00

I hope this will make the code a little more readable.

Signed-off-by: Masahiro Yamada 
Reviewed-by: Marek Vasut 
Signed-off-by: Boris Brezillon

mtd: remove unneeded initializer in mtd_ooblayout_{get, set}_bytes()

2016-11-19T18:31:29+00:00

There is no need to initialize oobregion and section since they will
be filled by mtd_ooblayout_find_region().

Signed-off-by: Masahiro Yamada 
Reviewed-by: Marek Vasut 
Signed-off-by: Boris Brezillon

treewide: remove redundant #include

2016-10-11T22:06:33+00:00

Kernel source files need not include  explicitly
because the top Makefile forces to include it with:

  -include $(srctree)/include/linux/kconfig.h

This commit removes explicit includes except the following:

  * arch/s390/include/asm/facilities_src.h
  * tools/testing/radix-tree/linux/kernel.h

These two are used for host programs.

Link: http://lkml.kernel.org/r/1473656164-11929-1-git-send-email-yamada.masahiro@socionext.com
Signed-off-by: Masahiro Yamada 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mtd: introduce the mtd_pairing_scheme concept

2016-09-15T14:47:56+00:00

MLC and TLC NAND devices are using NAND cells exposing more than one bit,
but instead of attaching all the bits in a given cell to a single NAND
page, each bit is usually attached to a different page. This concept is
called 'page pairing', and has significant impacts on the flash storage
usage.
The main problem showed by these devices is that interrupting a page
program operation may not only corrupt the page we are programming
but also the page it is paired with, hence the need to expose to MTD
users the pairing scheme information.

The pairing APIs allows one to query pairing information attached to a
given page (here called wunit), or the other way around (the wunit
pointed by pairing information).
It also provides several helpers to help the conversion between absolute
offsets and wunits, and query the number of pairing groups.

Signed-off-by: Boris Brezillon 
Reviewed-by: Brian Norris

mtd: kill the nand_ecclayout struct

2016-05-05T21:51:51+00:00

Now that all MTD drivers have moved to the mtd_ooblayout_ops model we can
safely remove the struct nand_ecclayout definition, and all the remaining
places where it was still used.

Signed-off-by: Boris Brezillon

mtd: create an mtd_ooblayout_ops struct to ease ECC layout definition

2016-04-19T20:05:55+00:00

ECC layout definitions are currently exposed using the nand_ecclayout
struct which embeds oobfree and eccpos arrays with predefined size.
This approach was acceptable when NAND chips were providing relatively
small OOB regions, but MLC and TLC now provide OOB regions of several
hundreds of bytes, which implies a non negligible overhead for everybody
even those who only need to support legacy NANDs.

Create an mtd_ooblayout_ops interface providing the same functionality
(expose the ECC and oobfree layout) without the need for this huge
structure.

The mtd->ecclayout is now deprecated and should be replaced by the
equivalent mtd_ooblayout_ops. In the meantime we provide a wrapper around
the ->ecclayout field to ease migration to this new model.

Signed-off-by: Boris Brezillon

mtd: add mtd_ooblayout_xxx() helper functions

2016-04-19T20:05:47+00:00

In order to make the ecclayout definition completely dynamic we need to
rework the way the OOB layout are defined and iterated.

Create a few mtd_ooblayout_xxx() helpers to ease OOB bytes manipulation
and hide ecclayout internals to their users.

Signed-off-by: Boris Brezillon

mtd: Hook I/O activity to the MTD LED trigger

2016-04-13T08:23:16+00:00

Now that we've added the MTD LED trigger, we need
to call each I/O path to ledtrig_mtd_activity.

Signed-off-by: Ezequiel Garcia 
Acked-by: Boris Brezillon 
Signed-off-by: Jacek Anaszewski