linux-toradex.git/drivers/mtd/mtdpart.c, branch v4.4.90

mtd: mtdpart: Do not fail mtd probe when parsing partitions fails

2015-10-27T01:43:48+00:00

Due to wrong assumption in ofpart ofpart fails on Exynos on SPI chips
with no partitions because the subnode containing controller data
confuses the ofpart parser.

Thus compiling in ofpart support automatically fails probing any SPI NOR
flash without partitions on Exynos.

Compiling in a partitioning scheme should not cause probe of otherwise
valid device to fail.

Instead, let's do the following:
 * try parsers until one succeeds
 * if no parser succeeds, report the first error we saw
 * even in the failure case, allow MTD to probe, with fallback
   partitions or no partitions at all -- the master device will still be
   registered

Issue report and comments initially by Michal Suchanek.

Reported-by: Michal Suchanek 
Signed-off-by: Brian Norris

mtd: mtdpart: add debug prints to partition parser.

2015-10-11T19:58:28+00:00

The probe of a mtd device can fail when a partition parser returns
error. The failure due to partition parsing can be quite mysterious when
multiple partitioning schemes are compiled in and any of them can fail
the probe.

Add debug prints which show what parsers were tried and what they
returned.

Signed-off-by: Michal Suchanek 
Signed-off-by: Brian Norris

mtd: mtdpart: fix add_mtd_partitions error path

2015-09-30T16:49:07+00:00

If we fail to allocate a partition structure in the middle of the partition
creation process, the already allocated partitions are never removed, which
means they are still present in the partition list and their resources are
never freed.

Signed-off-by: Boris Brezillon 
Cc: stable@vger.kernel.org
Signed-off-by: Brian Norris

mtd: part: Remove partition overlap checks

2015-04-06T00:44:03+00:00

This patch makes MTD dynamic partitioning more flexible by removing
overlap checks for dynamic partitions. I don't see any  particular
reason why overlapping dynamic partitions should be prohibited while
static partitions are allowed to overlap freely.

The checks previously had an off-by-one error, where 'end' should be
one less than what it is currently set at, and adding partitions out of
increasing order will fail. Disabling the checks resolves this issue.

Signed-off-by: Dan Ehrenberg 
Signed-off-by: Brian Norris

mtd: part: Add sysfs variable for offset of partition

2015-04-06T00:44:02+00:00

This patch makes a sysfs variable called 'offset' on each partition
which contains the offset in bytes from the beginning of the master
device that the partition starts.

Signed-off-by: Dan Ehrenberg 
Signed-off-by: Brian Norris

mtd: part: Create the master device node when partitioned

2015-04-06T00:44:01+00:00

For many use cases, it helps to have a device node for the entire
MTD device as well as device nodes for the individual partitions.
For example, this allows querying the entire device's properties.
A common idiom is to create an additional partition which spans
over the whole device.

This patch makes a config option, CONFIG_MTD_PARTITIONED_MASTER,
which makes the master partition present even when the device is
partitioned. This isn't turned on by default since it presents
a backwards-incompatible device numbering.

The patch also makes the parent of a partition device be the master,
if the config flag is set, now that the master is a full device.

Signed-off-by: Dan Ehrenberg 
Signed-off-by: Brian Norris

fs: introduce f_op->mmap_capabilities for nommu mmap support

2015-01-20T21:02:58+00:00

Since "BDI: Provide backing device capability information [try #3]" the
backing_dev_info structure also provides flags for the kind of mmap
operation available in a nommu environment, which is entirely unrelated
to it's original purpose.

Introduce a new nommu-only file operation to provide this information to
the nommu mmap code instead.  Splitting this from the backing_dev_info
structure allows to remove lots of backing_dev_info instance that aren't
otherwise needed, and entirely gets rid of the concept of providing a
backing_dev_info for a character device.  It also removes the need for
the mtd_inodefs filesystem.

Signed-off-by: Christoph Hellwig 
Reviewed-by: Tejun Heo 
Acked-by: Brian Norris 
Signed-off-by: Jens Axboe

mtd: Account for BBT blocks when a partition is being allocated

2014-07-09T01:38:29+00:00

With the introduction of mtd_block_isreserved(), it's now possible
to fix the bad and reserved block distribution exposed by ecc_stats,
instead of accounting all the bad or reserved blocks as 'bad'.

Signed-off-by: Ezequiel Garcia 
Tested-by: Pekon Gupta 
Signed-off-by: Brian Norris

mtd: Introduce mtd_block_isreserved()

2014-07-09T01:38:16+00:00

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 
Tested-by: Pekon Gupta 
Signed-off-by: Brian Norris

mtd: Add a retlen parameter to _get_{fact,user}_prot_info

2014-03-11T05:42:28+00:00

Signed-off-by: Christian Riesch 
Cc: Artem Bityutskiy 
Signed-off-by: Brian Norris