Hi, I wrote this patch for KVM [1], but now that I look closer it seems like there might be some overlapping functionality.
First there's emulate_instruction(), but since that only handles a few instructions it's just an ordered list of if ((instruction & MASK_A) == INST_A) tests, so it doesn't actually parse out opcodes or anything. I've also found xmon's ppc-opc.c. That parses the opcode and operands, so could use some shared macros. Of course, the actual lookup isn't time-sensitive, so that doesn't make sense to share. On the other hand, if we do come up with something fast *and* robust for KVM, maybe xmon could use that. Of course, these macros alone is pretty small, so maybe it's not a big deal to make a kvm-specific copy of them, leaving the other uses alone. Comments? [1] KVM on PowerPC traps when privileged instructions are executed in the guest context. We must then (quickly!) disassemble them and emulate their behavior. Right now we do this with a giant switch statement or two, but are considering more sophisticated techniques in the future. -- Hollis Blanchard IBM Linux Technology Center
ppc: Create disassemble.h to extract instruction fields This is used in a couple places in KVM, but isn't KVM-specific. Signed-off-by: Hollis Blanchard <[EMAIL PROTECTED]> diff --git a/arch/powerpc/include/asm/disassemble.h b/arch/powerpc/include/asm/disassemble.h new file mode 100644 --- /dev/null +++ b/arch/powerpc/include/asm/disassemble.h @@ -0,0 +1,80 @@ +/* + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License, version 2, as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. + * + * Copyright IBM Corp. 2008 + * + * Authors: Hollis Blanchard <[EMAIL PROTECTED]> + */ + +#ifndef __ASM_PPC_DISASSEMBLE_H__ +#define __ASM_PPC_DISASSEMBLE_H__ + +#include <linux/types.h> + +static inline unsigned int get_op(u32 inst) +{ + return inst >> 26; +} + +static inline unsigned int get_xop(u32 inst) +{ + return (inst >> 1) & 0x3ff; +} + +static inline unsigned int get_sprn(u32 inst) +{ + return ((inst >> 16) & 0x1f) | ((inst >> 6) & 0x3e0); +} + +static inline unsigned int get_dcrn(u32 inst) +{ + return ((inst >> 16) & 0x1f) | ((inst >> 6) & 0x3e0); +} + +static inline unsigned int get_rt(u32 inst) +{ + return (inst >> 21) & 0x1f; +} + +static inline unsigned int get_rs(u32 inst) +{ + return (inst >> 21) & 0x1f; +} + +static inline unsigned int get_ra(u32 inst) +{ + return (inst >> 16) & 0x1f; +} + +static inline unsigned int get_rb(u32 inst) +{ + return (inst >> 11) & 0x1f; +} + +static inline unsigned int get_rc(u32 inst) +{ + return inst & 0x1; +} + +static inline unsigned int get_ws(u32 inst) +{ + return (inst >> 11) & 0x1f; +} + +static inline unsigned int get_d(u32 inst) +{ + return inst & 0xffff; +} + +#endif /* __ASM_PPC_DISASSEMBLE_H__ */ diff --git a/arch/powerpc/kvm/emulate.c b/arch/powerpc/kvm/emulate.c --- a/arch/powerpc/kvm/emulate.c +++ b/arch/powerpc/kvm/emulate.c @@ -28,62 +28,7 @@ #include <asm/time.h> #include <asm/byteorder.h> #include <asm/kvm_ppc.h> - -/* Instruction decoding */ -static inline unsigned int get_op(u32 inst) -{ - return inst >> 26; -} - -static inline unsigned int get_xop(u32 inst) -{ - return (inst >> 1) & 0x3ff; -} - -static inline unsigned int get_sprn(u32 inst) -{ - return ((inst >> 16) & 0x1f) | ((inst >> 6) & 0x3e0); -} - -static inline unsigned int get_dcrn(u32 inst) -{ - return ((inst >> 16) & 0x1f) | ((inst >> 6) & 0x3e0); -} - -static inline unsigned int get_rt(u32 inst) -{ - return (inst >> 21) & 0x1f; -} - -static inline unsigned int get_rs(u32 inst) -{ - return (inst >> 21) & 0x1f; -} - -static inline unsigned int get_ra(u32 inst) -{ - return (inst >> 16) & 0x1f; -} - -static inline unsigned int get_rb(u32 inst) -{ - return (inst >> 11) & 0x1f; -} - -static inline unsigned int get_rc(u32 inst) -{ - return inst & 0x1; -} - -static inline unsigned int get_ws(u32 inst) -{ - return (inst >> 11) & 0x1f; -} - -static inline unsigned int get_d(u32 inst) -{ - return inst & 0xffff; -} +#include <asm/disassemble.h> static void kvmppc_emulate_dec(struct kvm_vcpu *vcpu) {