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| author | Paul Mackerras <paulus@samba.org> | 2011-12-12 12:36:37 +0000 |
|---|---|---|
| committer | Avi Kivity <avi@redhat.com> | 2012-03-05 14:52:37 +0200 |
| commit | 697d3899dcb4bcd918d060a92db57b794e56b077 (patch) | |
| tree | 173cdd849eca204fec8b64ea520b619372c3d970 /arch/powerpc/include/asm/mmu-hash64.h | |
| parent | 06ce2c63d933e347f8a199f123a8a293619ab3d2 (diff) | |
| download | lwn-697d3899dcb4bcd918d060a92db57b794e56b077.tar.gz lwn-697d3899dcb4bcd918d060a92db57b794e56b077.zip | |
KVM: PPC: Implement MMIO emulation support for Book3S HV guests
This provides the low-level support for MMIO emulation in Book3S HV
guests. When the guest tries to map a page which is not covered by
any memslot, that page is taken to be an MMIO emulation page. Instead
of inserting a valid HPTE, we insert an HPTE that has the valid bit
clear but another hypervisor software-use bit set, which we call
HPTE_V_ABSENT, to indicate that this is an absent page. An
absent page is treated much like a valid page as far as guest hcalls
(H_ENTER, H_REMOVE, H_READ etc.) are concerned, except of course that
an absent HPTE doesn't need to be invalidated with tlbie since it
was never valid as far as the hardware is concerned.
When the guest accesses a page for which there is an absent HPTE, it
will take a hypervisor data storage interrupt (HDSI) since we now set
the VPM1 bit in the LPCR. Our HDSI handler for HPTE-not-present faults
looks up the hash table and if it finds an absent HPTE mapping the
requested virtual address, will switch to kernel mode and handle the
fault in kvmppc_book3s_hv_page_fault(), which at present just calls
kvmppc_hv_emulate_mmio() to set up the MMIO emulation.
This is based on an earlier patch by Benjamin Herrenschmidt, but since
heavily reworked.
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
Diffstat (limited to 'arch/powerpc/include/asm/mmu-hash64.h')
| -rw-r--r-- | arch/powerpc/include/asm/mmu-hash64.h | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/arch/powerpc/include/asm/mmu-hash64.h b/arch/powerpc/include/asm/mmu-hash64.h index 412ba493cb98..0759dd8bf5aa 100644 --- a/arch/powerpc/include/asm/mmu-hash64.h +++ b/arch/powerpc/include/asm/mmu-hash64.h @@ -108,11 +108,11 @@ extern char initial_stab[]; #define HPTE_V_VRMA_MASK ASM_CONST(0x4001ffffff000000) /* Values for PP (assumes Ks=0, Kp=1) */ -/* pp0 will always be 0 for linux */ #define PP_RWXX 0 /* Supervisor read/write, User none */ #define PP_RWRX 1 /* Supervisor read/write, User read */ #define PP_RWRW 2 /* Supervisor read/write, User read/write */ #define PP_RXRX 3 /* Supervisor read, User read */ +#define PP_RXXX (HPTE_R_PP0 | 2) /* Supervisor read, user none */ #ifndef __ASSEMBLY__ |