BMC/Intel-BMC/linux.git/arch/arm/mm/idmap.c, branch dev

ARM: 8152/1: Convert pr_warning to pr_warn

2014-09-26T13:39:53+00:00

Use the more common pr_warn. Other miscellanea: o Coalesce formats o Realign arguments Signed-off-by: Joe Perches Signed-off-by: Russell King

ARM: idmap: add identity mapping usage note

2014-08-02T14:20:26+00:00

Add a note about the usage of the identity mapping; we do not support accesses outside of the identity map region and kernel image while a CPU is using the identity map. This is because the identity mapping may overwrite vmalloc space, IO mappings, the vectors pages, etc. Acked-by: Will Deacon Signed-off-by: Russell King

ARM: 8115/1: LPAE: reduce damage caused by idmap to virtual memory layout

2014-07-29T12:00:04+00:00

On LPAE, each level 1 (pgd) page table entry maps 1GiB, and the level 2 (pmd) entries map 2MiB. When the identity mapping is created on LPAE, the pgd pointers are copied from the swapper_pg_dir. If we find that we need to modify the contents of a pmd, we allocate a new empty pmd table and insert it into the appropriate 1GB slot, before then filling it with the identity mapping. However, if the 1GB slot covers the kernel lowmem mappings, we obliterate those mappings. When replacing a PMD, first copy the old PMD contents to the new PMD, so that we preserve the existing mappings, particularly the mappings of the kernel itself. [rewrote commit message and added code comment -- rmk] Fixes: ae2de101739c ("ARM: LPAE: Add identity mapping support for the 3-level page table format") Signed-off-by: Konstantin Khlebnikov Signed-off-by: Russell King

ARM: mm: Move the idmap print to appropriate place in the code

2013-10-11T00:25:06+00:00

Commit 9e9a367c29cebd2 {ARM: Section based HYP idmap} moved the address conversion inside identity_mapping_add() without respective print which carries useful idmap information. Move the print as well inside identity_mapping_add() to fix the same. Cc: Will Deacon Cc: Nicolas Pitre Cc: Russell King Signed-off-by: Santosh Shilimkar

ARM: mm: Introduce virt_to_idmap() with an arch hook

2013-10-11T00:25:06+00:00

On some PAE systems (e.g. TI Keystone), memory is above the 32-bit addressable limit, and the interconnect provides an aliased view of parts of physical memory in the 32-bit addressable space. This alias is strictly for boot time usage, and is not otherwise usable because of coherency limitations. On such systems, the idmap mechanism needs to take this aliased mapping into account. This patch introduces virt_to_idmap() and a arch function pointer which can be populated by platform which needs it. Also populate necessary idmap spots with now available virt_to_idmap(). Avoided #ifdef approach to be compatible with multi-platform builds. Most architecture won't touch it and in that case virt_to_idmap() fall-back to existing virt_to_phys() macro. Cc: Russell King Acked-by: Nicolas Pitre Signed-off-by: Santosh Shilimkar

ARM: KVM: move to a KVM provided HYP idmap

2013-04-29T05:23:08+00:00

After the HYP page table rework, it is pretty easy to let the KVM code provide its own idmap, rather than expecting the kernel to provide it. It takes actually less code to do so. Acked-by: Will Deacon Signed-off-by: Marc Zyngier Signed-off-by: Christoffer Dall

ARM: 7661/1: mm: perform explicit branch predictor maintenance when required

2013-03-03T22:54:16+00:00

The ARM ARM requires branch predictor maintenance if, for a given ASID, the instructions at a specific virtual address appear to change. From the kernel's point of view, that means: - Changing the kernel's view of memory (e.g. switching to the identity map) - ASID rollover (since ASIDs will be re-allocated to new tasks) This patch adds explicit branch predictor maintenance when either of the two conditions above are met. Reviewed-by: Catalin Marinas Signed-off-by: Will Deacon Signed-off-by: Russell King

ARM: Section based HYP idmap

2013-01-23T18:29:09+00:00

Add a method (hyp_idmap_setup) to populate a hyp pgd with an identity mapping of the code contained in the .hyp.idmap.text section. Offer a method to drop this identity mapping through hyp_idmap_teardown. Make all the above depend on CONFIG_ARM_VIRT_EXT and CONFIG_ARM_LPAE. Reviewed-by: Will Deacon Reviewed-by: Marcelo Tosatti Signed-off-by: Marc Zyngier Signed-off-by: Christoffer Dall

ARM: 7573/1: idmap: use flush_cache_louis() and flush TLBs only when necessary

2012-11-13T11:47:41+00:00

Flushing the cache is needed for the hardware to see the idmap table and therefore can be done at init time. On ARMv7 it is not necessary to flush L2 so flush_cache_louis() is used here instead. There is no point flushing the cache in setup_mm_for_reboot() as the caller should, and already is, taking care of this. If switching the memory map requires a cache flush, then cpu_switch_mm() already includes that operation. What is not done by cpu_switch_mm() on ASID capable CPUs is TLB flushing as the whole point of the ASID is to tag the TLBs and avoid flushing them on a context switch. Since we don't have a clean ASID for the identity mapping, we need to flush the TLB explicitly in that case. Otherwise this is already performed by cpu_switch_mm(). Signed-off-by: Nicolas Pitre Acked-by: Will Deacon Signed-off-by: Russell King

Disintegrate asm/system.h for ARM

2012-03-28T17:30:01+00:00

Disintegrate asm/system.h for ARM. Signed-off-by: David Howells cc: Russell King cc: linux-arm-kernel@lists.infradead.org