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Subject[PATCH 2/5] x86: Share definition of __is_canonical_address()
Date
Reduce code duplication by moving canonical address code to a common header
file.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
---
arch/x86/events/intel/pt.c | 14 ++------------
arch/x86/include/asm/page.h | 10 ++++++++++
arch/x86/kvm/emulate.c | 4 ++--
arch/x86/kvm/x86.c | 2 +-
arch/x86/kvm/x86.h | 7 +------
arch/x86/mm/maccess.c | 7 +------
6 files changed, 17 insertions(+), 27 deletions(-)

diff --git a/arch/x86/events/intel/pt.c b/arch/x86/events/intel/pt.c
index 4443de56a2d5..4015c1364463 100644
--- a/arch/x86/events/intel/pt.c
+++ b/arch/x86/events/intel/pt.c
@@ -1366,20 +1366,10 @@ static void pt_addr_filters_fini(struct perf_event *event)
}

#ifdef CONFIG_X86_64
-static u64 canonical_address(u64 vaddr, u8 vaddr_bits)
-{
- return ((s64)vaddr << (64 - vaddr_bits)) >> (64 - vaddr_bits);
-}
-
-static u64 is_canonical_address(u64 vaddr, u8 vaddr_bits)
-{
- return canonical_address(vaddr, vaddr_bits) == vaddr;
-}
-
/* Clamp to a canonical address greater-than-or-equal-to the address given */
static u64 clamp_to_ge_canonical_addr(u64 vaddr, u8 vaddr_bits)
{
- return is_canonical_address(vaddr, vaddr_bits) ?
+ return __is_canonical_address(vaddr, vaddr_bits) ?
vaddr :
-BIT_ULL(vaddr_bits - 1);
}
@@ -1387,7 +1377,7 @@ static u64 clamp_to_ge_canonical_addr(u64 vaddr, u8 vaddr_bits)
/* Clamp to a canonical address less-than-or-equal-to the address given */
static u64 clamp_to_le_canonical_addr(u64 vaddr, u8 vaddr_bits)
{
- return is_canonical_address(vaddr, vaddr_bits) ?
+ return __is_canonical_address(vaddr, vaddr_bits) ?
vaddr :
BIT_ULL(vaddr_bits - 1) - 1;
}
diff --git a/arch/x86/include/asm/page.h b/arch/x86/include/asm/page.h
index 4d5810c8fab7..9cc82f305f4b 100644
--- a/arch/x86/include/asm/page.h
+++ b/arch/x86/include/asm/page.h
@@ -71,6 +71,16 @@ static inline void copy_user_page(void *to, void *from, unsigned long vaddr,
extern bool __virt_addr_valid(unsigned long kaddr);
#define virt_addr_valid(kaddr) __virt_addr_valid((unsigned long) (kaddr))

+static __always_inline u64 __canonical_address(u64 vaddr, u8 vaddr_bits)
+{
+ return ((s64)vaddr << (64 - vaddr_bits)) >> (64 - vaddr_bits);
+}
+
+static __always_inline u64 __is_canonical_address(u64 vaddr, u8 vaddr_bits)
+{
+ return __canonical_address(vaddr, vaddr_bits) == vaddr;
+}
+
#endif /* __ASSEMBLY__ */

#include <asm-generic/memory_model.h>
diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
index 5719d8cfdbd9..40da8c7f3019 100644
--- a/arch/x86/kvm/emulate.c
+++ b/arch/x86/kvm/emulate.c
@@ -665,7 +665,7 @@ static inline u8 ctxt_virt_addr_bits(struct x86_emulate_ctxt *ctxt)
static inline bool emul_is_noncanonical_address(u64 la,
struct x86_emulate_ctxt *ctxt)
{
- return get_canonical(la, ctxt_virt_addr_bits(ctxt)) != la;
+ return !__is_canonical_address(la, ctxt_virt_addr_bits(ctxt));
}

/*
@@ -715,7 +715,7 @@ static __always_inline int __linearize(struct x86_emulate_ctxt *ctxt,
case X86EMUL_MODE_PROT64:
*linear = la;
va_bits = ctxt_virt_addr_bits(ctxt);
- if (get_canonical(la, va_bits) != la)
+ if (!__is_canonical_address(la, va_bits))
goto bad;

*max_size = min_t(u64, ~0u, (1ull << va_bits) - la);
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 9e43d756312f..af15a7065aa7 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -1735,7 +1735,7 @@ static int __kvm_set_msr(struct kvm_vcpu *vcpu, u32 index, u64 data,
* value, and that something deterministic happens if the guest
* invokes 64-bit SYSENTER.
*/
- data = get_canonical(data, vcpu_virt_addr_bits(vcpu));
+ data = __canonical_address(data, vcpu_virt_addr_bits(vcpu));
break;
case MSR_TSC_AUX:
if (!kvm_is_supported_user_return_msr(MSR_TSC_AUX))
diff --git a/arch/x86/kvm/x86.h b/arch/x86/kvm/x86.h
index 635b75f9e145..fc4b68ab8d71 100644
--- a/arch/x86/kvm/x86.h
+++ b/arch/x86/kvm/x86.h
@@ -211,14 +211,9 @@ static inline u8 vcpu_virt_addr_bits(struct kvm_vcpu *vcpu)
return kvm_read_cr4_bits(vcpu, X86_CR4_LA57) ? 57 : 48;
}

-static inline u64 get_canonical(u64 la, u8 vaddr_bits)
-{
- return ((int64_t)la << (64 - vaddr_bits)) >> (64 - vaddr_bits);
-}
-
static inline bool is_noncanonical_address(u64 la, struct kvm_vcpu *vcpu)
{
- return get_canonical(la, vcpu_virt_addr_bits(vcpu)) != la;
+ return !__is_canonical_address(la, vcpu_virt_addr_bits(vcpu));
}

static inline void vcpu_cache_mmio_info(struct kvm_vcpu *vcpu,
diff --git a/arch/x86/mm/maccess.c b/arch/x86/mm/maccess.c
index 92ec176a7293..5a53c2cc169c 100644
--- a/arch/x86/mm/maccess.c
+++ b/arch/x86/mm/maccess.c
@@ -4,11 +4,6 @@
#include <linux/kernel.h>

#ifdef CONFIG_X86_64
-static __always_inline u64 canonical_address(u64 vaddr, u8 vaddr_bits)
-{
- return ((s64)vaddr << (64 - vaddr_bits)) >> (64 - vaddr_bits);
-}
-
bool copy_from_kernel_nofault_allowed(const void *unsafe_src, size_t size)
{
unsigned long vaddr = (unsigned long)unsafe_src;
@@ -19,7 +14,7 @@ bool copy_from_kernel_nofault_allowed(const void *unsafe_src, size_t size)
* we also need to include the userspace guard page.
*/
return vaddr >= TASK_SIZE_MAX + PAGE_SIZE &&
- canonical_address(vaddr, boot_cpu_data.x86_virt_bits) == vaddr;
+ __is_canonical_address(vaddr, boot_cpu_data.x86_virt_bits);
}
#else
bool copy_from_kernel_nofault_allowed(const void *unsafe_src, size_t size)
--
2.25.1
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