Commit Graph

5 Commits

Author SHA1 Message Date
Ard Biesheuvel 9f1dcbe8c8 ArmPkg/ArmMmuLib ARM: implement memory permission control routines
Now that we have the prerequisite functionality available in ArmMmuLib,
wire it up into ArmSetMemoryRegionNoExec, ArmClearMemoryRegionNoExec,
ArmSetMemoryRegionReadOnly and ArmClearMemoryRegionReadOnly. This is
used by the non-executable stack feature that is configured by DxeIpl.

NOTE: The current implementation will not combine RO and XP attributes,
      i.e., setting/clearing a region no-exec will unconditionally
      clear the read-only attribute, and vice versa. Currently, we
      only use ArmSetMemoryRegionNoExec(), so for now, we should be
      able to live with this.

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Leif Lindholm <leif.lindholm@linaro.org>
2017-03-07 10:31:53 +01:00
Ard Biesheuvel d9c0d991f7 ArmPkg/ArmMmuLib: remove VirtualMask arg from ArmSetMemoryAttributes
We no longer make use of the ArmMmuLib 'feature' to create aliased
memory ranges with mismatched attributes, and in fact, it was only
wired up in the ARM version to begin with.

So remove the VirtualMask argument from ArmSetMemoryAttributes()'s
prototype, and remove the dead code that referred to it.

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Leif Lindholm <leif.lindholm@linaro.org>
2017-03-07 09:38:08 +01:00
Ard Biesheuvel 521f3cedac ArmPkg: move ARM version of SetMemoryAttributes to ArmMmuLib
... where it belongs, since AARCH64 already keeps it there, and
non DXE users of ArmMmuLib (such as DxeIpl, for the non-executable
stack) may need its functionality as well.

While at it, rename SetMemoryAttributes to ArmSetMemoryAttributes,
and make any functions that are not exported STATIC. Also, replace
an explicit gBS->AllocatePages() call [which is DXE specific] with
MemoryAllocationLib::AllocatePages().

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Leif Lindholm <leif.lindholm@linaro.org>
2017-03-07 09:38:08 +01:00
Ard Biesheuvel f49ea03de7 ArmPkg/ArmMmuLib: use correct return type for exported functions
The routines ArmConfigureMmu(), SetMemoryAttributes() [*] and the
various set/clear read-only/no-exec routines are declared as returning
EFI_STATUS in the respective header files, so align the definitions with
that.

* SetMemoryAttributes() is declared in the wrong header (and defined in
  ArmMmuLib for AARCH64 and in CpuDxe for ARM)

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Leif Lindholm <leif.lindholm@linaro.org>
2017-03-07 09:37:09 +01:00
Ard Biesheuvel d7f03464b2 ArmPkg: introduce base ArmMmuLib implementation
This base library encapsulates the MMU manipulation routines that have been
factored out of ArmLib. The functionality covers initial creation of the 1:1
mapping in the page tables, and remapping regions to change permissions or
cacheability attributes.

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Leif Lindholm <leif.lindholm@linaro.org>
2016-07-07 14:33:47 +02:00