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| author | Marc Zyngier <marc.zyngier@arm.com> | 2017-04-03 19:37:50 +0100 |
|---|---|---|
| committer | Christoffer Dall <cdall@linaro.org> | 2017-04-09 07:49:26 -0700 |
| commit | cf763e4ede9deca45c83d7a59c8e798c4d079da2 (patch) | |
| tree | 2e50d4a1a986d0b79598950b99bed30132ac4f4c /arch | |
| parent | 6b52f7bdb8883b9c6a47a5558e6b08834c952fb3 (diff) | |
| download | linux-cf763e4ede9deca45c83d7a59c8e798c4d079da2.tar.bz2 | |
ARM: Expose the VA/IDMAP offset
The KVM code needs to be able to compute the address of
symbols in its idmap page (the equivalent of a virt_to_idmap()
call). Unfortunately, virt_to_idmap is slightly complicated,
depending on the use of arch_phys_to_idmap_offset or not, and
none of that is readily available at HYP.
Instead, expose a single kimage_voffset variable which contains the
offset between a kernel VA and its idmap address, enabling the
VA->IDMAP conversion. This allows the KVM code to behave similarily
to its arm64 counterpart.
Tested-by: Keerthy <j-keerthy@ti.com>
Acked-by: Russell King <rmk+kernel@armlinux.org.uk>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <cdall@linaro.org>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/arm/mm/mmu.c | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/arch/arm/mm/mmu.c b/arch/arm/mm/mmu.c index 4e016d7f37b3..e98a2b5c4e85 100644 --- a/arch/arm/mm/mmu.c +++ b/arch/arm/mm/mmu.c @@ -87,6 +87,8 @@ struct cachepolicy { #define s2_policy(policy) 0 #endif +unsigned long kimage_voffset __ro_after_init; + static struct cachepolicy cache_policies[] __initdata = { { .policy = "uncached", @@ -1635,4 +1637,7 @@ void __init paging_init(const struct machine_desc *mdesc) empty_zero_page = virt_to_page(zero_page); __flush_dcache_page(NULL, empty_zero_page); + + /* Compute the virt/idmap offset, mostly for the sake of KVM */ + kimage_voffset = (unsigned long)&kimage_voffset - virt_to_idmap(&kimage_voffset); } |