[PATCH 0/4] Consolidate identity mapping code in idmap.c

[Dave Martin]

On Wed, Nov 16, 2011 at 04:48:10PM +0000, Will Deacon wrote:
> Hello,
> 
> This patch series consolidates the identity mapping code into idmap.c,
> where a single set of page tables (idmap_pgd) are allocated and populated
> at init time for use by subsystems such as soft reboot, kexec and CPU
> suspend.
> 
> A new linker section (.idmap.text) is introduced so that code which
> needs to be identity mapped can be annotated with __idmap or, if written
> in assembly, placed there explicitly.
> 
> CPU suspend, cpu_*_reset and setup_mm_for_reboot are all updated to work
> with the new mapping code.
> 
> This is currently based on 3.2-rc2, but will be based on Russell's reset
> branch when it comes to merging (where the prototype of
> setup_mm_for_reboot has changed slightly). Furthermore, I have rebased
> my kexec series against this which I will post separately.
> 
> Comments welcome.

I haven't exhaustively checked every detail, but this looks like a
cleaner, more scalabale and more robust way to handle code which needs
to be identity-mapped compared with what we had previously; so I'm in
favour of it.

FWIW

Acked-by: Dave Martin <dave.martin at linaro.org>

> 
> Cheers,
> 
> Will
> 
> 
> Will Deacon (4):
>   ARM: idmap: populate identity map pgd at init time using .init.text
>   ARM: suspend: use idmap_pgd instead of suspend_pgd
>   ARM: proc-*.S: place cpu_reset functions into .idmap.text section
>   ARM: idmap: use idmap_pgd when setting up mm for reboot
> 
>  arch/arm/include/asm/idmap.h      |   11 ++++++++
>  arch/arm/kernel/sleep.S           |    2 +
>  arch/arm/kernel/suspend.c         |   17 ++----------
>  arch/arm/kernel/vmlinux.lds.S     |    1 +
>  arch/arm/mm/idmap.c               |   49 ++++++++++++++++++++++++++++++-------
>  arch/arm/mm/proc-arm1020.S        |    3 ++
>  arch/arm/mm/proc-arm1020e.S       |    3 ++
>  arch/arm/mm/proc-arm1022.S        |    3 ++
>  arch/arm/mm/proc-arm1026.S        |    3 ++
>  arch/arm/mm/proc-arm6_7.S         |    4 +++
>  arch/arm/mm/proc-arm720.S         |    3 ++
>  arch/arm/mm/proc-arm740.S         |    3 ++
>  arch/arm/mm/proc-arm7tdmi.S       |    3 ++
>  arch/arm/mm/proc-arm920.S         |    3 ++
>  arch/arm/mm/proc-arm922.S         |    3 ++
>  arch/arm/mm/proc-arm925.S         |    3 ++
>  arch/arm/mm/proc-arm926.S         |    3 ++
>  arch/arm/mm/proc-arm940.S         |    3 ++
>  arch/arm/mm/proc-arm946.S         |    3 ++
>  arch/arm/mm/proc-arm9tdmi.S       |    3 ++
>  arch/arm/mm/proc-fa526.S          |    3 ++
>  arch/arm/mm/proc-feroceon.S       |    3 ++
>  arch/arm/mm/proc-mohawk.S         |    3 ++
>  arch/arm/mm/proc-sa110.S          |    3 ++
>  arch/arm/mm/proc-sa1100.S         |    3 ++
>  arch/arm/mm/proc-v6.S             |    3 ++
>  arch/arm/mm/proc-v7.S             |    2 +
>  arch/arm/mm/proc-xsc3.S           |    3 ++
>  arch/arm/mm/proc-xscale.S         |    3 ++
>  include/asm-generic/vmlinux.lds.h |    6 ++++
>  30 files changed, 135 insertions(+), 23 deletions(-)
>  create mode 100644 arch/arm/include/asm/idmap.h
> 
> -- 
> 1.7.4.1
> 
> 
> _______________________________________________
> linux-arm-kernel mailing list
> linux-arm-kernel at lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel