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path: root/arch/powerpc/kvm/44x_tlb.h
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2009-03-24KVM: ppc: rename 44x MMU functions used in booke.cHollis Blanchard
e500 will provide its own implementation of these. Signed-off-by: Hollis Blanchard <hollisb@us.ibm.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2009-03-24KVM: ppc: turn tlb_xlate() into a per-core hook (and give it a better name)Hollis Blanchard
Signed-off-by: Hollis Blanchard <hollisb@us.ibm.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31KVM: ppc: directly insert shadow mappings into the hardware TLBHollis Blanchard
Formerly, we used to maintain a per-vcpu shadow TLB and on every entry to the guest would load this array into the hardware TLB. This consumed 1280 bytes of memory (64 entries of 16 bytes plus a struct page pointer each), and also required some assembly to loop over the array on every entry. Instead of saving a copy in memory, we can just store shadow mappings directly into the hardware TLB, accepting that the host kernel will clobber these as part of the normal 440 TLB round robin. When we do that we need less than half the memory, and we have decreased the exit handling time for all guest exits, at the cost of increased number of TLB misses because the host overwrites some guest entries. These savings will be increased on processors with larger TLBs or which implement intelligent flush instructions like tlbivax (which will avoid the need to walk arrays in software). In addition to that and to the code simplification, we have a greater chance of leaving other host userspace mappings in the TLB, instead of forcing all subsequent tasks to re-fault all their mappings. Signed-off-by: Hollis Blanchard <hollisb@us.ibm.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31KVM: ppc: refactor instruction emulation into generic and core-specific piecesHollis Blanchard
Cores provide 3 emulation hooks, implemented for example in the new 4xx_emulate.c: kvmppc_core_emulate_op kvmppc_core_emulate_mtspr kvmppc_core_emulate_mfspr Strictly speaking the last two aren't necessary, but provide for more informative error reporting ("unknown SPR"). Long term I'd like to have instruction decoding autogenerated from tables of opcodes, and that way we could aggregate universal, Book E, and core-specific instructions more easily and without redundant switch statements. Signed-off-by: Hollis Blanchard <hollisb@us.ibm.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31KVM: ppc: Refactor powerpc.c to relocate 440-specific codeHollis Blanchard
This introduces a set of core-provided hooks. For 440, some of these are implemented by booke.c, with the rest in (the new) 44x.c. Note that these hooks are link-time, not run-time. Since it is not possible to build a single kernel for both e500 and 440 (for example), using function pointers would only add overhead. Signed-off-by: Hollis Blanchard <hollisb@us.ibm.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31KVM: ppc: Rename "struct tlbe" to "struct kvmppc_44x_tlbe"Hollis Blanchard
This will ease ports to other cores. Also remove unused "struct kvm_tlb" while we're at it. Signed-off-by: Hollis Blanchard <hollisb@us.ibm.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2008-04-27KVM: ppc: PowerPC 440 KVM implementationHollis Blanchard
This functionality is definitely experimental, but is capable of running unmodified PowerPC 440 Linux kernels as guests on a PowerPC 440 host. (Only tested with 440EP "Bamboo" guests so far, but with appropriate userspace support other SoC/board combinations should work.) See Documentation/powerpc/kvm_440.txt for technical details. [stephen: build fix] Signed-off-by: Hollis Blanchard <hollisb@us.ibm.com> Acked-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Avi Kivity <avi@qumranet.com>