linux/arch/mips/kvm/dyntrans.c
Paul Gortmaker cd14c92bbd MIPS: kvm: Audit and remove any unnecessary uses of module.h
Historically a lot of these existed because we did not have
a distinction between what was modular code and what was providing
support to modules via EXPORT_SYMBOL and friends.  That changed
when we forked out support for the latter into the export.h file.

This means we should be able to reduce the usage of module.h
in code that is obj-y Makefile or bool Kconfig.  In the case of
kvm where it is modular, we can extend that to also include files
that are building basic support functionality but not related
to loading or registering the final module; such files also have
no need whatsoever for module.h

The advantage in removing such instances is that module.h itself
sources about 15 other headers; adding significantly to what we feed
cpp, and it can obscure what headers we are effectively using.

Since module.h was the source for init.h (for __init) and for
export.h (for EXPORT_SYMBOL) we consider each instance for the
presence of either and replace as needed.  In this case, we did
not need to add either to any files.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Acked-by: James Hogan <james.hogan@imgtec.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: kvm@vger.kernel.org
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14036/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-10-05 01:31:20 +02:00

134 lines
3.8 KiB
C

/*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
* KVM/MIPS: Binary Patching for privileged instructions, reduces traps.
*
* Copyright (C) 2012 MIPS Technologies, Inc. All rights reserved.
* Authors: Sanjay Lal <sanjayl@kymasys.com>
*/
#include <linux/errno.h>
#include <linux/err.h>
#include <linux/highmem.h>
#include <linux/kvm_host.h>
#include <linux/vmalloc.h>
#include <linux/fs.h>
#include <linux/bootmem.h>
#include <asm/cacheflush.h>
#include "commpage.h"
/**
* kvm_mips_trans_replace() - Replace trapping instruction in guest memory.
* @vcpu: Virtual CPU.
* @opc: PC of instruction to replace.
* @replace: Instruction to write
*/
static int kvm_mips_trans_replace(struct kvm_vcpu *vcpu, u32 *opc,
union mips_instruction replace)
{
unsigned long paddr, flags;
void *vaddr;
if (KVM_GUEST_KSEGX((unsigned long)opc) == KVM_GUEST_KSEG0) {
paddr = kvm_mips_translate_guest_kseg0_to_hpa(vcpu,
(unsigned long)opc);
vaddr = kmap_atomic(pfn_to_page(PHYS_PFN(paddr)));
vaddr += paddr & ~PAGE_MASK;
memcpy(vaddr, (void *)&replace, sizeof(u32));
local_flush_icache_range((unsigned long)vaddr,
(unsigned long)vaddr + 32);
kunmap_atomic(vaddr);
} else if (KVM_GUEST_KSEGX((unsigned long) opc) == KVM_GUEST_KSEG23) {
local_irq_save(flags);
memcpy((void *)opc, (void *)&replace, sizeof(u32));
__local_flush_icache_user_range((unsigned long)opc,
(unsigned long)opc + 32);
local_irq_restore(flags);
} else {
kvm_err("%s: Invalid address: %p\n", __func__, opc);
return -EFAULT;
}
return 0;
}
int kvm_mips_trans_cache_index(union mips_instruction inst, u32 *opc,
struct kvm_vcpu *vcpu)
{
union mips_instruction nop_inst = { 0 };
/* Replace the CACHE instruction, with a NOP */
return kvm_mips_trans_replace(vcpu, opc, nop_inst);
}
/*
* Address based CACHE instructions are transformed into synci(s). A little
* heavy for just D-cache invalidates, but avoids an expensive trap
*/
int kvm_mips_trans_cache_va(union mips_instruction inst, u32 *opc,
struct kvm_vcpu *vcpu)
{
union mips_instruction synci_inst = { 0 };
synci_inst.i_format.opcode = bcond_op;
synci_inst.i_format.rs = inst.i_format.rs;
synci_inst.i_format.rt = synci_op;
if (cpu_has_mips_r6)
synci_inst.i_format.simmediate = inst.spec3_format.simmediate;
else
synci_inst.i_format.simmediate = inst.i_format.simmediate;
return kvm_mips_trans_replace(vcpu, opc, synci_inst);
}
int kvm_mips_trans_mfc0(union mips_instruction inst, u32 *opc,
struct kvm_vcpu *vcpu)
{
union mips_instruction mfc0_inst = { 0 };
u32 rd, sel;
rd = inst.c0r_format.rd;
sel = inst.c0r_format.sel;
if (rd == MIPS_CP0_ERRCTL && sel == 0) {
mfc0_inst.r_format.opcode = spec_op;
mfc0_inst.r_format.rd = inst.c0r_format.rt;
mfc0_inst.r_format.func = add_op;
} else {
mfc0_inst.i_format.opcode = lw_op;
mfc0_inst.i_format.rt = inst.c0r_format.rt;
mfc0_inst.i_format.simmediate = KVM_GUEST_COMMPAGE_ADDR |
offsetof(struct kvm_mips_commpage, cop0.reg[rd][sel]);
#ifdef CONFIG_CPU_BIG_ENDIAN
if (sizeof(vcpu->arch.cop0->reg[0][0]) == 8)
mfc0_inst.i_format.simmediate |= 4;
#endif
}
return kvm_mips_trans_replace(vcpu, opc, mfc0_inst);
}
int kvm_mips_trans_mtc0(union mips_instruction inst, u32 *opc,
struct kvm_vcpu *vcpu)
{
union mips_instruction mtc0_inst = { 0 };
u32 rd, sel;
rd = inst.c0r_format.rd;
sel = inst.c0r_format.sel;
mtc0_inst.i_format.opcode = sw_op;
mtc0_inst.i_format.rt = inst.c0r_format.rt;
mtc0_inst.i_format.simmediate = KVM_GUEST_COMMPAGE_ADDR |
offsetof(struct kvm_mips_commpage, cop0.reg[rd][sel]);
#ifdef CONFIG_CPU_BIG_ENDIAN
if (sizeof(vcpu->arch.cop0->reg[0][0]) == 8)
mtc0_inst.i_format.simmediate |= 4;
#endif
return kvm_mips_trans_replace(vcpu, opc, mtc0_inst);
}