On Sun, Oct 18, 2020 at 11:18 PM <[email protected]> wrote: > > From: Shuo Liu <[email protected]> > > The Service VM communicates with the hypervisor via conventional > hypercalls. VMCALL instruction is used to make the hypercalls. > > ACRN hypercall ABI: > * Hypercall number is in R8 register. > * Up to 2 parameters are in RDI and RSI registers. > * Return value is in RAX register. > > Introduce the ACRN hypercall interfaces. Because GCC doesn't support R8 > register as direct register constraints, use supported constraint as > input with a explicit MOV to R8 in beginning of asm.
Reviewed-by: Nick Desaulniers <[email protected]> > > Originally-by: Yakui Zhao <[email protected]> > Signed-off-by: Shuo Liu <[email protected]> > Reviewed-by: Reinette Chatre <[email protected]> > Cc: Dave Hansen <[email protected]> > Cc: Sean Christopherson <[email protected]> > Cc: Dan Williams <[email protected]> > Cc: Fengwei Yin <[email protected]> > Cc: Zhi Wang <[email protected]> > Cc: Zhenyu Wang <[email protected]> > Cc: Yu Wang <[email protected]> > Cc: Reinette Chatre <[email protected]> > Cc: Greg Kroah-Hartman <[email protected]> > Cc: Borislav Petkov <[email protected]> > Cc: Arvind Sankar <[email protected]> > Cc: Peter Zijlstra <[email protected]> > Cc: Nick Desaulniers <[email protected]> > Cc: Segher Boessenkool <[email protected]> > --- > arch/x86/include/asm/acrn.h | 54 +++++++++++++++++++++++++++++++++++++ > 1 file changed, 54 insertions(+) > > diff --git a/arch/x86/include/asm/acrn.h b/arch/x86/include/asm/acrn.h > index a2d4aea3a80d..03e420245505 100644 > --- a/arch/x86/include/asm/acrn.h > +++ b/arch/x86/include/asm/acrn.h > @@ -14,4 +14,58 @@ void acrn_setup_intr_handler(void (*handler)(void)); > void acrn_remove_intr_handler(void); > bool acrn_is_privileged_vm(void); > > +/* > + * Hypercalls for ACRN > + * > + * - VMCALL instruction is used to implement ACRN hypercalls. > + * - ACRN hypercall ABI: > + * - Hypercall number is passed in R8 register. > + * - Up to 2 arguments are passed in RDI, RSI. > + * - Return value will be placed in RAX. > + * > + * Because GCC doesn't support R8 register as direct register constraints, > use > + * supported constraint as input with a explicit MOV to R8 in beginning of > asm. > + */ > +static inline long acrn_hypercall0(unsigned long hcall_id) > +{ > + long result; > + > + asm volatile("movl %1, %%r8d\n\t" > + "vmcall\n\t" > + : "=a" (result) > + : "ir" (hcall_id) > + : "r8", "memory"); > + > + return result; > +} > + > +static inline long acrn_hypercall1(unsigned long hcall_id, > + unsigned long param1) > +{ > + long result; > + > + asm volatile("movl %1, %%r8d\n\t" > + "vmcall\n\t" > + : "=a" (result) > + : "ir" (hcall_id), "D" (param1) > + : "r8", "memory"); > + > + return result; > +} > + > +static inline long acrn_hypercall2(unsigned long hcall_id, > + unsigned long param1, > + unsigned long param2) > +{ > + long result; > + > + asm volatile("movl %1, %%r8d\n\t" > + "vmcall\n\t" > + : "=a" (result) > + : "ir" (hcall_id), "D" (param1), "S" (param2) > + : "r8", "memory"); > + > + return result; > +} > + > #endif /* _ASM_X86_ACRN_H */ > -- > 2.28.0 > -- Thanks, ~Nick Desaulniers
