kernel/linux.git/drivers/mtd/mtdpart.c, branch v3.4.84

mtd: mtdpart: break it as soon as we parse out the partitions

2012-10-12T20:38:58+00:00

commit c51803ddba10d80d9f246066802c6e359cf1d44c upstream. We may cause a memory leak when the @types has more then one parser. Take the `default_mtd_part_types` for example. The default_mtd_part_types has two parsers now: `cmdlinepart` and `ofpart`. Assume the following case: The kernel command line sets the partitions like: #gpmi-nand:20m(boot),20m(kernel),1g(rootfs),-(user) But the devicetree file(such as arch/arm/boot/dts/imx28-evk.dts) also sets the same partitions as the kernel command line does. In the current code, the partitions parsed out by the `ofpart` will overwrite the @pparts which has already set by the `cmdlinepart` parser, and the the partitions parsed out by the `cmdlinepart` is missed. A memory leak occurs. So we should break the code as soon as we parse out the partitions, In actually, this patch makes a priority order between the parsers. If one parser has already parsed out the partitions successfully, it's no need to use another parser anymore. Signed-off-by: Huang Shijie Signed-off-by: Artem Bityutskiy Signed-off-by: David Woodhouse Signed-off-by: Greg Kroah-Hartman

mtd: flash drivers set ecc strength

2012-03-26T23:56:46+00:00

Flash device drivers initialize 'ecc_strength' in struct mtd_info, which is the maximum number of bit errors that can be corrected in one writesize region. Drivers using the nand interface intitialize 'strength' in struct nand_ecc_ctrl, which is the maximum number of bit errors that can be corrected in one ecc step. Nand infrastructure code translates this to 'ecc_strength'. Also for nand drivers, the nand infrastructure code sets ecc.strength for ecc modes NAND_ECC_SOFT, NAND_ECC_SOFT_BCH, and NAND_ECC_NONE. It is set in the driver for all other modes. Signed-off-by: Mike Dunn Signed-off-by: Artem Bityutskiy Signed-off-by: David Woodhouse

mtd: fix partition wrapper functions

2012-03-26T23:44:29+00:00

This patch reverts a change that may have been mistakenly included with the set of patches that introduced the new mtd api entry functions. Or perhaps I am mistaken :) The problem is in the partition wrapper functions, where the calls to the driver methods were replaced with calls to the new mtd api functions. This causes the api function to be called a second time, further down the call stack. This is not only unnecessary and redundant - because the sanity checking code and (more restrictive) bounds checks for the partition were done in the first call - but is potentially problematic and confusing. For example, the call stack for a call to mtd_read() on a partitioned device currently looks like this: mtd_read() gets struct mtd_info for the partition | +-> part_read() via the pointer assigned when the partition was created | +->mtd_read() this time gets struct mtd_info for the master | +->xyz_driver_read() via the pointer asigned by the driver It seems that this can cause a variety of problems. For example, if you want to add code to the api function that tests a value in mtd_info that is relevant only to the partition. Or (in my case) you want the driver to return a value that may be different from that returned by the mtd api function. This patch eliminates the second call to the mtd api function. It was tested on the docg4 nand driver with a subset of the api functions, but I inspected the rest and don't see any problems. Signed-off-by: Mike Dunn Signed-off-by: Artem Bityutskiy Signed-off-by: David Woodhouse

mtd: remove R/O checking duplication

2012-03-26T23:29:11+00:00

Many drivers check whether the partition is R/O and return -EROFS if yes. Let's stop having duplicated checks and move them to the API functions instead. And again a bit of noise - deleted few too sparse newlines, sorry. Signed-off-by: Artem Bityutskiy Signed-off-by: David Woodhouse

mtd: do not duplicate length and offset checks in drivers

2012-03-26T23:28:18+00:00

We already verify that offset and length are within the MTD device size in the MTD API functions. Let's remove the duplicated checks in drivers. This patch only affects the following API's: 'mtd_erase()' 'mtd_point()' 'mtd_unpoint()' 'mtd_get_unmapped_area()' 'mtd_read()' 'mtd_write()' 'mtd_panic_write()' 'mtd_lock()' 'mtd_unlock()' 'mtd_is_locked()' 'mtd_block_isbad()' 'mtd_block_markbad()' This patch adds a bit of noise by removing too sparse empty lines, but this is not too bad. Signed-off-by: Artem Bityutskiy Signed-off-by: David Woodhouse

mtd: return error code from mtd_unpoint

2012-03-26T23:27:19+00:00

The 'mtd_unpoint()' API function should be able to return an error code because it may fail if you specify incorrect offset. This patch changes this MTD API function and amends all the drivers correspondingly. Also return '-EOPNOTSUPP' from 'mtd_unpoint()' when the '->unpoint()' method is undefined. We do not really need this currently, but this just makes sense to be consistent with 'mtd_point()'. Signed-off-by: Artem Bityutskiy Signed-off-by: David Woodhouse

mtd: add leading underscore to all mtd functions

2012-03-26T23:20:01+00:00

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 Signed-off-by: David Woodhouse

mtd: minor coding style cleanup in mtdpart.c

2012-03-26T23:16:24+00:00

Signed-off-by: Stefan Roese Signed-off-by: Artem Bityutskiy Signed-off-by: David Woodhouse

mtd: introduce mtd_block_markbad interface

2012-01-09T18:25:48+00:00

Signed-off-by: Artem Bityutskiy Signed-off-by: David Woodhouse

mtd: introduce mtd_block_isbad interface

2012-01-09T18:25:47+00:00

Signed-off-by: Artem Bityutskiy Signed-off-by: David Woodhouse