linux/arch/powerpc/kvm/book3s_rmhandlers.S
Alexander Graf 2b05d71fef KVM: PPC: Make long relocations be ulong
On Book3S KVM we directly expose some asm pointers to C code as
variables. These need to be relocated and thus break on relocatable
kernels.

To make sure we can at least build, let's mark them as long instead
of u32 where 64bit relocations don't work.

This fixes the following build error:

WARNING: 2 bad relocations^M
> c000000000008590 R_PPC64_ADDR32    .text+0x4000000000008460^M
> c000000000008594 R_PPC64_ADDR32    .text+0x4000000000008598^M

Please keep in mind that actually using KVM on a relocated kernel
might still break. This only fixes the compile problem.

Reported-by: Subrata Modak <subrata@linux.vnet.ibm.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-10-24 10:50:59 +02:00

262 lines
6.7 KiB
ArmAsm

/*
* 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 SUSE Linux Products GmbH 2009
*
* Authors: Alexander Graf <agraf@suse.de>
*/
#include <asm/ppc_asm.h>
#include <asm/kvm_asm.h>
#include <asm/reg.h>
#include <asm/page.h>
#include <asm/asm-offsets.h>
#ifdef CONFIG_PPC_BOOK3S_64
#include <asm/exception-64s.h>
#endif
/*****************************************************************************
* *
* Real Mode handlers that need to be in low physical memory *
* *
****************************************************************************/
#if defined(CONFIG_PPC_BOOK3S_64)
#define LOAD_SHADOW_VCPU(reg) \
mfspr reg, SPRN_SPRG_PACA
#define SHADOW_VCPU_OFF PACA_KVM_SVCPU
#define MSR_NOIRQ MSR_KERNEL & ~(MSR_IR | MSR_DR)
#define FUNC(name) GLUE(.,name)
#elif defined(CONFIG_PPC_BOOK3S_32)
#define LOAD_SHADOW_VCPU(reg) \
mfspr reg, SPRN_SPRG_THREAD; \
lwz reg, THREAD_KVM_SVCPU(reg); \
/* PPC32 can have a NULL pointer - let's check for that */ \
mtspr SPRN_SPRG_SCRATCH1, r12; /* Save r12 */ \
mfcr r12; \
cmpwi reg, 0; \
bne 1f; \
mfspr reg, SPRN_SPRG_SCRATCH0; \
mtcr r12; \
mfspr r12, SPRN_SPRG_SCRATCH1; \
b kvmppc_resume_\intno; \
1:; \
mtcr r12; \
mfspr r12, SPRN_SPRG_SCRATCH1; \
tophys(reg, reg)
#define SHADOW_VCPU_OFF 0
#define MSR_NOIRQ MSR_KERNEL
#define FUNC(name) name
#endif
.macro INTERRUPT_TRAMPOLINE intno
.global kvmppc_trampoline_\intno
kvmppc_trampoline_\intno:
mtspr SPRN_SPRG_SCRATCH0, r13 /* Save r13 */
/*
* First thing to do is to find out if we're coming
* from a KVM guest or a Linux process.
*
* To distinguish, we check a magic byte in the PACA/current
*/
LOAD_SHADOW_VCPU(r13)
PPC_STL r12, (SHADOW_VCPU_OFF + SVCPU_SCRATCH0)(r13)
mfcr r12
stw r12, (SHADOW_VCPU_OFF + SVCPU_SCRATCH1)(r13)
lbz r12, (SHADOW_VCPU_OFF + SVCPU_IN_GUEST)(r13)
cmpwi r12, KVM_GUEST_MODE_NONE
bne ..kvmppc_handler_hasmagic_\intno
/* No KVM guest? Then jump back to the Linux handler! */
lwz r12, (SHADOW_VCPU_OFF + SVCPU_SCRATCH1)(r13)
mtcr r12
PPC_LL r12, (SHADOW_VCPU_OFF + SVCPU_SCRATCH0)(r13)
mfspr r13, SPRN_SPRG_SCRATCH0 /* r13 = original r13 */
b kvmppc_resume_\intno /* Get back original handler */
/* Now we know we're handling a KVM guest */
..kvmppc_handler_hasmagic_\intno:
/* Should we just skip the faulting instruction? */
cmpwi r12, KVM_GUEST_MODE_SKIP
beq kvmppc_handler_skip_ins
/* Let's store which interrupt we're handling */
li r12, \intno
/* Jump into the SLB exit code that goes to the highmem handler */
b kvmppc_handler_trampoline_exit
.endm
INTERRUPT_TRAMPOLINE BOOK3S_INTERRUPT_SYSTEM_RESET
INTERRUPT_TRAMPOLINE BOOK3S_INTERRUPT_MACHINE_CHECK
INTERRUPT_TRAMPOLINE BOOK3S_INTERRUPT_DATA_STORAGE
INTERRUPT_TRAMPOLINE BOOK3S_INTERRUPT_INST_STORAGE
INTERRUPT_TRAMPOLINE BOOK3S_INTERRUPT_EXTERNAL
INTERRUPT_TRAMPOLINE BOOK3S_INTERRUPT_ALIGNMENT
INTERRUPT_TRAMPOLINE BOOK3S_INTERRUPT_PROGRAM
INTERRUPT_TRAMPOLINE BOOK3S_INTERRUPT_FP_UNAVAIL
INTERRUPT_TRAMPOLINE BOOK3S_INTERRUPT_DECREMENTER
INTERRUPT_TRAMPOLINE BOOK3S_INTERRUPT_SYSCALL
INTERRUPT_TRAMPOLINE BOOK3S_INTERRUPT_TRACE
INTERRUPT_TRAMPOLINE BOOK3S_INTERRUPT_PERFMON
INTERRUPT_TRAMPOLINE BOOK3S_INTERRUPT_ALTIVEC
/* Those are only available on 64 bit machines */
#ifdef CONFIG_PPC_BOOK3S_64
INTERRUPT_TRAMPOLINE BOOK3S_INTERRUPT_DATA_SEGMENT
INTERRUPT_TRAMPOLINE BOOK3S_INTERRUPT_INST_SEGMENT
INTERRUPT_TRAMPOLINE BOOK3S_INTERRUPT_VSX
#endif
/*
* Bring us back to the faulting code, but skip the
* faulting instruction.
*
* This is a generic exit path from the interrupt
* trampolines above.
*
* Input Registers:
*
* R12 = free
* R13 = Shadow VCPU (PACA)
* SVCPU.SCRATCH0 = guest R12
* SVCPU.SCRATCH1 = guest CR
* SPRG_SCRATCH0 = guest R13
*
*/
kvmppc_handler_skip_ins:
/* Patch the IP to the next instruction */
mfsrr0 r12
addi r12, r12, 4
mtsrr0 r12
/* Clean up all state */
lwz r12, (SHADOW_VCPU_OFF + SVCPU_SCRATCH1)(r13)
mtcr r12
PPC_LL r12, (SHADOW_VCPU_OFF + SVCPU_SCRATCH0)(r13)
mfspr r13, SPRN_SPRG_SCRATCH0
/* And get back into the code */
RFI
/*
* This trampoline brings us back to a real mode handler
*
* Input Registers:
*
* R5 = SRR0
* R6 = SRR1
* LR = real-mode IP
*
*/
.global kvmppc_handler_lowmem_trampoline
kvmppc_handler_lowmem_trampoline:
mtsrr0 r5
mtsrr1 r6
blr
kvmppc_handler_lowmem_trampoline_end:
/*
* Call a function in real mode
*
* Input Registers:
*
* R3 = function
* R4 = MSR
* R5 = scratch register
*
*/
_GLOBAL(kvmppc_rmcall)
LOAD_REG_IMMEDIATE(r5, MSR_NOIRQ)
mtmsr r5 /* Disable relocation and interrupts, so mtsrr
doesn't get interrupted */
sync
mtsrr0 r3
mtsrr1 r4
RFI
#if defined(CONFIG_PPC_BOOK3S_32)
#define STACK_LR INT_FRAME_SIZE+4
/* load_up_xxx have to run with MSR_DR=0 on Book3S_32 */
#define MSR_EXT_START \
PPC_STL r20, _NIP(r1); \
mfmsr r20; \
LOAD_REG_IMMEDIATE(r3, MSR_DR|MSR_EE); \
andc r3,r20,r3; /* Disable DR,EE */ \
mtmsr r3; \
sync
#define MSR_EXT_END \
mtmsr r20; /* Enable DR,EE */ \
sync; \
PPC_LL r20, _NIP(r1)
#elif defined(CONFIG_PPC_BOOK3S_64)
#define STACK_LR _LINK
#define MSR_EXT_START
#define MSR_EXT_END
#endif
/*
* Activate current's external feature (FPU/Altivec/VSX)
*/
#define define_load_up(what) \
\
_GLOBAL(kvmppc_load_up_ ## what); \
PPC_STLU r1, -INT_FRAME_SIZE(r1); \
mflr r3; \
PPC_STL r3, STACK_LR(r1); \
MSR_EXT_START; \
\
bl FUNC(load_up_ ## what); \
\
MSR_EXT_END; \
PPC_LL r3, STACK_LR(r1); \
mtlr r3; \
addi r1, r1, INT_FRAME_SIZE; \
blr
define_load_up(fpu)
#ifdef CONFIG_ALTIVEC
define_load_up(altivec)
#endif
#ifdef CONFIG_VSX
define_load_up(vsx)
#endif
.global kvmppc_trampoline_lowmem
kvmppc_trampoline_lowmem:
PPC_LONG kvmppc_handler_lowmem_trampoline - CONFIG_KERNEL_START
.global kvmppc_trampoline_enter
kvmppc_trampoline_enter:
PPC_LONG kvmppc_handler_trampoline_enter - CONFIG_KERNEL_START
#include "book3s_segment.S"