Skip to content

Commit

Permalink
powerpc/64: Allow for relocation-on interrupts from guest to host
Browse files Browse the repository at this point in the history
With host and guest both using radix translation, it is feasible
for the host to take interrupts that come from the guest with
relocation on, and that is in fact what the POWER9 hardware will
do when LPCR[AIL] = 3.  All such interrupts use HSRR0/1 not SRR0/1
except for system call with LEV=1 (hcall).

Therefore this adds the KVM tests to the _HV variants of the
relocation-on interrupt handlers, and adds the KVM test to the
relocation-on system call entry point.

We also instantiate the relocation-on versions of the hypervisor
data storage and instruction interrupt handlers, since these can
occur with relocation on in radix guests.

Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
  • Loading branch information
Paul Mackerras authored and Michael Ellerman committed Jan 31, 2017
1 parent 16ed141 commit bc35512
Show file tree
Hide file tree
Showing 2 changed files with 34 additions and 29 deletions.
10 changes: 5 additions & 5 deletions arch/powerpc/include/asm/exception-64s.h
Original file line number Diff line number Diff line change
Expand Up @@ -428,12 +428,12 @@ END_FTR_SECTION_NESTED(ftr,ftr,943)
EXCEPTION_RELON_PROLOG_PSERIES_1(label, EXC_STD)

#define STD_RELON_EXCEPTION_HV(loc, vec, label) \
/* No guest interrupts come through here */ \
SET_SCRATCH0(r13); /* save r13 */ \
EXCEPTION_RELON_PROLOG_PSERIES(PACA_EXGEN, label, EXC_HV, NOTEST, vec);
EXCEPTION_RELON_PROLOG_PSERIES(PACA_EXGEN, label, \
EXC_HV, KVMTEST_HV, vec);

#define STD_RELON_EXCEPTION_HV_OOL(vec, label) \
EXCEPTION_PROLOG_1(PACA_EXGEN, NOTEST, vec); \
EXCEPTION_PROLOG_1(PACA_EXGEN, KVMTEST_HV, vec); \
EXCEPTION_RELON_PROLOG_PSERIES_1(label, EXC_HV)

/* This associate vector numbers with bits in paca->irq_happened */
Expand Down Expand Up @@ -510,10 +510,10 @@ END_FTR_SECTION_NESTED(ftr,ftr,943)

#define MASKABLE_RELON_EXCEPTION_HV(loc, vec, label) \
_MASKABLE_RELON_EXCEPTION_PSERIES(vec, label, \
EXC_HV, SOFTEN_NOTEST_HV)
EXC_HV, SOFTEN_TEST_HV)

#define MASKABLE_RELON_EXCEPTION_HV_OOL(vec, label) \
EXCEPTION_PROLOG_1(PACA_EXGEN, SOFTEN_NOTEST_HV, vec); \
EXCEPTION_PROLOG_1(PACA_EXGEN, SOFTEN_TEST_HV, vec); \
EXCEPTION_PROLOG_PSERIES_1(label, EXC_HV)

/*
Expand Down
53 changes: 29 additions & 24 deletions arch/powerpc/kernel/exceptions-64s.S
Original file line number Diff line number Diff line change
Expand Up @@ -830,6 +830,31 @@ EXC_VIRT(trap_0b, 0x4b00, 0x4c00, 0xb00)
TRAMP_KVM(PACA_EXGEN, 0xb00)
EXC_COMMON(trap_0b_common, 0xb00, unknown_exception)

#ifdef CONFIG_KVM_BOOK3S_64_HANDLER
/*
* If CONFIG_KVM_BOOK3S_64_HANDLER is set, save the PPR (on systems
* that support it) before changing to HMT_MEDIUM. That allows the KVM
* code to save that value into the guest state (it is the guest's PPR
* value). Otherwise just change to HMT_MEDIUM as userspace has
* already saved the PPR.
*/
#define SYSCALL_KVMTEST \
SET_SCRATCH0(r13); \
GET_PACA(r13); \
std r9,PACA_EXGEN+EX_R9(r13); \
OPT_GET_SPR(r9, SPRN_PPR, CPU_FTR_HAS_PPR); \
HMT_MEDIUM; \
std r10,PACA_EXGEN+EX_R10(r13); \
OPT_SAVE_REG_TO_PACA(PACA_EXGEN+EX_PPR, r9, CPU_FTR_HAS_PPR); \
mfcr r9; \
KVMTEST_PR(0xc00); \
GET_SCRATCH0(r13)

#else
#define SYSCALL_KVMTEST \
HMT_MEDIUM
#endif

#define LOAD_SYSCALL_HANDLER(reg) \
__LOAD_HANDLER(reg, system_call_common)

Expand Down Expand Up @@ -883,34 +908,14 @@ END_FTR_SECTION_IFSET(CPU_FTR_REAL_LE) \
#endif

EXC_REAL_BEGIN(system_call, 0xc00, 0xd00)
/*
* If CONFIG_KVM_BOOK3S_64_HANDLER is set, save the PPR (on systems
* that support it) before changing to HMT_MEDIUM. That allows the KVM
* code to save that value into the guest state (it is the guest's PPR
* value). Otherwise just change to HMT_MEDIUM as userspace has
* already saved the PPR.
*/
#ifdef CONFIG_KVM_BOOK3S_64_HANDLER
SET_SCRATCH0(r13)
GET_PACA(r13)
std r9,PACA_EXGEN+EX_R9(r13)
OPT_GET_SPR(r9, SPRN_PPR, CPU_FTR_HAS_PPR);
HMT_MEDIUM;
std r10,PACA_EXGEN+EX_R10(r13)
OPT_SAVE_REG_TO_PACA(PACA_EXGEN+EX_PPR, r9, CPU_FTR_HAS_PPR);
mfcr r9
KVMTEST_PR(0xc00)
GET_SCRATCH0(r13)
#else
HMT_MEDIUM;
#endif
SYSCALL_KVMTEST
SYSCALL_PSERIES_1
SYSCALL_PSERIES_2_RFID
SYSCALL_PSERIES_3
EXC_REAL_END(system_call, 0xc00, 0xd00)

EXC_VIRT_BEGIN(system_call, 0x4c00, 0x4d00)
HMT_MEDIUM
SYSCALL_KVMTEST
SYSCALL_PSERIES_1
SYSCALL_PSERIES_2_DIRECT
SYSCALL_PSERIES_3
Expand All @@ -925,7 +930,7 @@ TRAMP_KVM(PACA_EXGEN, 0xd00)
EXC_COMMON(single_step_common, 0xd00, single_step_exception)

EXC_REAL_OOL_HV(h_data_storage, 0xe00, 0xe20)
EXC_VIRT_NONE(0x4e00, 0x4e20)
EXC_VIRT_OOL_HV(h_data_storage, 0x4e00, 0x4e20, 0xe00)
TRAMP_KVM_HV_SKIP(PACA_EXGEN, 0xe00)
EXC_COMMON_BEGIN(h_data_storage_common)
mfspr r10,SPRN_HDAR
Expand All @@ -941,7 +946,7 @@ EXC_COMMON_BEGIN(h_data_storage_common)


EXC_REAL_OOL_HV(h_instr_storage, 0xe20, 0xe40)
EXC_VIRT_NONE(0x4e20, 0x4e40)
EXC_VIRT_OOL_HV(h_instr_storage, 0x4e20, 0x4e40, 0xe20)
TRAMP_KVM_HV(PACA_EXGEN, 0xe20)
EXC_COMMON(h_instr_storage_common, 0xe20, unknown_exception)

Expand Down

0 comments on commit bc35512

Please sign in to comment.