BMC/Intel-BMC/linux.git/fs/pstore/ram_core.c, branch dev

pstore-ram: Allow optional mapping with pgprot_noncached

2014-12-11T21:38:31+00:00

On some ARMs the memory can be mapped pgprot_noncached() and still be working for atomic operations. As pointed out by Colin Cross , in some cases you do want to use pgprot_noncached() if the SoC supports it to see a debug printk just before a write hanging the system. On ARMs, the atomic operations on strongly ordered memory are implementation defined. So let's provide an optional kernel parameter for configuring pgprot_noncached(), and use pgprot_writecombine() by default. Cc: Arnd Bergmann Cc: Rob Herring Cc: Randy Dunlap Cc: Anton Vorontsov Cc: Colin Cross Cc: Olof Johansson Cc: Russell King Cc: stable@vger.kernel.org Acked-by: Kees Cook Signed-off-by: Tony Lindgren Signed-off-by: Tony Luck

pstore-ram: Fix hangs by using write-combine mappings

2014-12-11T21:35:49+00:00

Currently trying to use pstore on at least ARMs can hang as we're mapping the peristent RAM with pgprot_noncached(). On ARMs, pgprot_noncached() will actually make the memory strongly ordered, and as the atomic operations pstore uses are implementation defined for strongly ordered memory, they may not work. So basically atomic operations have undefined behavior on ARM for device or strongly ordered memory types. Let's fix the issue by using write-combine variants for mappings. This corresponds to normal, non-cacheable memory on ARM. For many other architectures, this change does not change the mapping type as by default we have: #define pgprot_writecombine pgprot_noncached The reason why pgprot_noncached() was originaly used for pstore is because Colin Cross had observed lost debug prints right before a device hanging write operation on some systems. For the platforms supporting pgprot_noncached(), we can add a an optional configuration option to support that. But let's get pstore working first before adding new features. Cc: Arnd Bergmann Cc: Anton Vorontsov Cc: Colin Cross Cc: Olof Johansson Cc: linux-kernel@vger.kernel.org Cc: stable@vger.kernel.org Acked-by: Kees Cook Signed-off-by: Rob Herring [tony@atomide.com: updated description] Signed-off-by: Tony Lindgren Signed-off-by: Tony Luck

fs/pstore/ram_core.c: replace count*size kmalloc by kmalloc_array

2014-08-08T22:57:25+00:00

kmalloc_array manages count*sizeof overflow. Signed-off-by: Fabian Frederick Cc: Anton Vorontsov Cc: Colin Cross Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

fs/pstore: logging clean-up

2014-06-06T23:08:13+00:00

- Define pr_fmt in plateform.c and ram_core.c for global prefix. - Coalesce format fragments. - Separate format/arguments on lines > 80 characters. Note: Some pr_foo() were initially declared without prefix and therefore this could break existing log analyzer. [akpm@linux-foundation.org: missed a couple of prefix removals] Signed-off-by: Fabian Frederick Cc: Joe Perches Cc: Anton Vorontsov Cc: Colin Cross Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

pstore: Fix buffer overflow while write offset equal to buffer size

2014-03-17T21:14:03+00:00

In case new offset is equal to prz->buffer_size, it won't wrap at this time and will return old(overflow) value next time. Signed-off-by: Liu ShuoX Acked-by: Kees Cook Signed-off-by: Tony Luck

pstore/ram: avoid atomic accesses for ioremapped regions

2013-06-14T22:54:21+00:00

For persistent RAM outside of main memory, the memory may have limitations on supported accesses. For internal RAM on highbank platform exclusive accesses are not supported and will hang the system. So atomic_cmpxchg cannot be used. This commit uses spinlock protection for buffer size and start updates on ioremapped regions instead. Signed-off-by: Rob Herring Acked-by: Anton Vorontsov Signed-off-by: Tony Luck

pstore/ram: Restore ecc information block

2013-04-04T04:50:10+00:00

This was lost when proc/last_kmsg moved to pstore/console-ramoops. Signed-off-by: Arve Hjønnevåg Signed-off-by: John Stultz Acked-by: Kees Cook Signed-off-by: Anton Vorontsov

pstore/ram: Allow specifying ecc parameters in platform data

2013-04-04T04:50:00+00:00

Allow specifying ecc parameters in platform data Signed-off-by: Arve Hjønnevåg [jstultz: Tweaked commit subject & add commit message] Signed-off-by: John Stultz Acked-by: Kees Cook Signed-off-by: Anton Vorontsov

pstore/ram: Include ecc_size when calculating ecc_block

2013-04-04T04:49:28+00:00

Wastes less memory and allows using more memory for ecc than data. Signed-off-by: Arve Hjønnevåg [jstultz: Tweaked commit subject] Signed-off-by: John Stultz Acked-by: Kees Cook Signed-off-by: Anton Vorontsov

pstore: remove __dev* attributes.

2013-01-03T23:57:14+00:00

CONFIG_HOTPLUG is going away as an option. As a result, the __dev* markings need to be removed. This change removes the use of __devinit from the pstore filesystem. Based on patches originally written by Bill Pemberton, but redone by me in order to handle some of the coding style issues better, by hand. Cc: Bill Pemberton Cc: Anton Vorontsov Cc: Colin Cross Cc: Kees Cook Cc: Tony Luck Signed-off-by: Greg Kroah-Hartman