mirror of https://github.com/Qortal/Brooklyn
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
721 lines
16 KiB
721 lines
16 KiB
// SPDX-License-Identifier: GPL-2.0-only |
|
/* |
|
* vMTRR implementation |
|
* |
|
* Copyright (C) 2006 Qumranet, Inc. |
|
* Copyright 2010 Red Hat, Inc. and/or its affiliates. |
|
* Copyright(C) 2015 Intel Corporation. |
|
* |
|
* Authors: |
|
* Yaniv Kamay <[email protected]> |
|
* Avi Kivity <[email protected]> |
|
* Marcelo Tosatti <[email protected]> |
|
* Paolo Bonzini <[email protected]> |
|
* Xiao Guangrong <[email protected]> |
|
*/ |
|
|
|
#include <linux/kvm_host.h> |
|
#include <asm/mtrr.h> |
|
|
|
#include "cpuid.h" |
|
#include "mmu.h" |
|
|
|
#define IA32_MTRR_DEF_TYPE_E (1ULL << 11) |
|
#define IA32_MTRR_DEF_TYPE_FE (1ULL << 10) |
|
#define IA32_MTRR_DEF_TYPE_TYPE_MASK (0xff) |
|
|
|
static bool msr_mtrr_valid(unsigned msr) |
|
{ |
|
switch (msr) { |
|
case 0x200 ... 0x200 + 2 * KVM_NR_VAR_MTRR - 1: |
|
case MSR_MTRRfix64K_00000: |
|
case MSR_MTRRfix16K_80000: |
|
case MSR_MTRRfix16K_A0000: |
|
case MSR_MTRRfix4K_C0000: |
|
case MSR_MTRRfix4K_C8000: |
|
case MSR_MTRRfix4K_D0000: |
|
case MSR_MTRRfix4K_D8000: |
|
case MSR_MTRRfix4K_E0000: |
|
case MSR_MTRRfix4K_E8000: |
|
case MSR_MTRRfix4K_F0000: |
|
case MSR_MTRRfix4K_F8000: |
|
case MSR_MTRRdefType: |
|
case MSR_IA32_CR_PAT: |
|
return true; |
|
} |
|
return false; |
|
} |
|
|
|
static bool valid_mtrr_type(unsigned t) |
|
{ |
|
return t < 8 && (1 << t) & 0x73; /* 0, 1, 4, 5, 6 */ |
|
} |
|
|
|
bool kvm_mtrr_valid(struct kvm_vcpu *vcpu, u32 msr, u64 data) |
|
{ |
|
int i; |
|
u64 mask; |
|
|
|
if (!msr_mtrr_valid(msr)) |
|
return false; |
|
|
|
if (msr == MSR_IA32_CR_PAT) { |
|
return kvm_pat_valid(data); |
|
} else if (msr == MSR_MTRRdefType) { |
|
if (data & ~0xcff) |
|
return false; |
|
return valid_mtrr_type(data & 0xff); |
|
} else if (msr >= MSR_MTRRfix64K_00000 && msr <= MSR_MTRRfix4K_F8000) { |
|
for (i = 0; i < 8 ; i++) |
|
if (!valid_mtrr_type((data >> (i * 8)) & 0xff)) |
|
return false; |
|
return true; |
|
} |
|
|
|
/* variable MTRRs */ |
|
WARN_ON(!(msr >= 0x200 && msr < 0x200 + 2 * KVM_NR_VAR_MTRR)); |
|
|
|
mask = kvm_vcpu_reserved_gpa_bits_raw(vcpu); |
|
if ((msr & 1) == 0) { |
|
/* MTRR base */ |
|
if (!valid_mtrr_type(data & 0xff)) |
|
return false; |
|
mask |= 0xf00; |
|
} else |
|
/* MTRR mask */ |
|
mask |= 0x7ff; |
|
|
|
return (data & mask) == 0; |
|
} |
|
EXPORT_SYMBOL_GPL(kvm_mtrr_valid); |
|
|
|
static bool mtrr_is_enabled(struct kvm_mtrr *mtrr_state) |
|
{ |
|
return !!(mtrr_state->deftype & IA32_MTRR_DEF_TYPE_E); |
|
} |
|
|
|
static bool fixed_mtrr_is_enabled(struct kvm_mtrr *mtrr_state) |
|
{ |
|
return !!(mtrr_state->deftype & IA32_MTRR_DEF_TYPE_FE); |
|
} |
|
|
|
static u8 mtrr_default_type(struct kvm_mtrr *mtrr_state) |
|
{ |
|
return mtrr_state->deftype & IA32_MTRR_DEF_TYPE_TYPE_MASK; |
|
} |
|
|
|
static u8 mtrr_disabled_type(struct kvm_vcpu *vcpu) |
|
{ |
|
/* |
|
* Intel SDM 11.11.2.2: all MTRRs are disabled when |
|
* IA32_MTRR_DEF_TYPE.E bit is cleared, and the UC |
|
* memory type is applied to all of physical memory. |
|
* |
|
* However, virtual machines can be run with CPUID such that |
|
* there are no MTRRs. In that case, the firmware will never |
|
* enable MTRRs and it is obviously undesirable to run the |
|
* guest entirely with UC memory and we use WB. |
|
*/ |
|
if (guest_cpuid_has(vcpu, X86_FEATURE_MTRR)) |
|
return MTRR_TYPE_UNCACHABLE; |
|
else |
|
return MTRR_TYPE_WRBACK; |
|
} |
|
|
|
/* |
|
* Three terms are used in the following code: |
|
* - segment, it indicates the address segments covered by fixed MTRRs. |
|
* - unit, it corresponds to the MSR entry in the segment. |
|
* - range, a range is covered in one memory cache type. |
|
*/ |
|
struct fixed_mtrr_segment { |
|
u64 start; |
|
u64 end; |
|
|
|
int range_shift; |
|
|
|
/* the start position in kvm_mtrr.fixed_ranges[]. */ |
|
int range_start; |
|
}; |
|
|
|
static struct fixed_mtrr_segment fixed_seg_table[] = { |
|
/* MSR_MTRRfix64K_00000, 1 unit. 64K fixed mtrr. */ |
|
{ |
|
.start = 0x0, |
|
.end = 0x80000, |
|
.range_shift = 16, /* 64K */ |
|
.range_start = 0, |
|
}, |
|
|
|
/* |
|
* MSR_MTRRfix16K_80000 ... MSR_MTRRfix16K_A0000, 2 units, |
|
* 16K fixed mtrr. |
|
*/ |
|
{ |
|
.start = 0x80000, |
|
.end = 0xc0000, |
|
.range_shift = 14, /* 16K */ |
|
.range_start = 8, |
|
}, |
|
|
|
/* |
|
* MSR_MTRRfix4K_C0000 ... MSR_MTRRfix4K_F8000, 8 units, |
|
* 4K fixed mtrr. |
|
*/ |
|
{ |
|
.start = 0xc0000, |
|
.end = 0x100000, |
|
.range_shift = 12, /* 12K */ |
|
.range_start = 24, |
|
} |
|
}; |
|
|
|
/* |
|
* The size of unit is covered in one MSR, one MSR entry contains |
|
* 8 ranges so that unit size is always 8 * 2^range_shift. |
|
*/ |
|
static u64 fixed_mtrr_seg_unit_size(int seg) |
|
{ |
|
return 8 << fixed_seg_table[seg].range_shift; |
|
} |
|
|
|
static bool fixed_msr_to_seg_unit(u32 msr, int *seg, int *unit) |
|
{ |
|
switch (msr) { |
|
case MSR_MTRRfix64K_00000: |
|
*seg = 0; |
|
*unit = 0; |
|
break; |
|
case MSR_MTRRfix16K_80000 ... MSR_MTRRfix16K_A0000: |
|
*seg = 1; |
|
*unit = array_index_nospec( |
|
msr - MSR_MTRRfix16K_80000, |
|
MSR_MTRRfix16K_A0000 - MSR_MTRRfix16K_80000 + 1); |
|
break; |
|
case MSR_MTRRfix4K_C0000 ... MSR_MTRRfix4K_F8000: |
|
*seg = 2; |
|
*unit = array_index_nospec( |
|
msr - MSR_MTRRfix4K_C0000, |
|
MSR_MTRRfix4K_F8000 - MSR_MTRRfix4K_C0000 + 1); |
|
break; |
|
default: |
|
return false; |
|
} |
|
|
|
return true; |
|
} |
|
|
|
static void fixed_mtrr_seg_unit_range(int seg, int unit, u64 *start, u64 *end) |
|
{ |
|
struct fixed_mtrr_segment *mtrr_seg = &fixed_seg_table[seg]; |
|
u64 unit_size = fixed_mtrr_seg_unit_size(seg); |
|
|
|
*start = mtrr_seg->start + unit * unit_size; |
|
*end = *start + unit_size; |
|
WARN_ON(*end > mtrr_seg->end); |
|
} |
|
|
|
static int fixed_mtrr_seg_unit_range_index(int seg, int unit) |
|
{ |
|
struct fixed_mtrr_segment *mtrr_seg = &fixed_seg_table[seg]; |
|
|
|
WARN_ON(mtrr_seg->start + unit * fixed_mtrr_seg_unit_size(seg) |
|
> mtrr_seg->end); |
|
|
|
/* each unit has 8 ranges. */ |
|
return mtrr_seg->range_start + 8 * unit; |
|
} |
|
|
|
static int fixed_mtrr_seg_end_range_index(int seg) |
|
{ |
|
struct fixed_mtrr_segment *mtrr_seg = &fixed_seg_table[seg]; |
|
int n; |
|
|
|
n = (mtrr_seg->end - mtrr_seg->start) >> mtrr_seg->range_shift; |
|
return mtrr_seg->range_start + n - 1; |
|
} |
|
|
|
static bool fixed_msr_to_range(u32 msr, u64 *start, u64 *end) |
|
{ |
|
int seg, unit; |
|
|
|
if (!fixed_msr_to_seg_unit(msr, &seg, &unit)) |
|
return false; |
|
|
|
fixed_mtrr_seg_unit_range(seg, unit, start, end); |
|
return true; |
|
} |
|
|
|
static int fixed_msr_to_range_index(u32 msr) |
|
{ |
|
int seg, unit; |
|
|
|
if (!fixed_msr_to_seg_unit(msr, &seg, &unit)) |
|
return -1; |
|
|
|
return fixed_mtrr_seg_unit_range_index(seg, unit); |
|
} |
|
|
|
static int fixed_mtrr_addr_to_seg(u64 addr) |
|
{ |
|
struct fixed_mtrr_segment *mtrr_seg; |
|
int seg, seg_num = ARRAY_SIZE(fixed_seg_table); |
|
|
|
for (seg = 0; seg < seg_num; seg++) { |
|
mtrr_seg = &fixed_seg_table[seg]; |
|
if (mtrr_seg->start <= addr && addr < mtrr_seg->end) |
|
return seg; |
|
} |
|
|
|
return -1; |
|
} |
|
|
|
static int fixed_mtrr_addr_seg_to_range_index(u64 addr, int seg) |
|
{ |
|
struct fixed_mtrr_segment *mtrr_seg; |
|
int index; |
|
|
|
mtrr_seg = &fixed_seg_table[seg]; |
|
index = mtrr_seg->range_start; |
|
index += (addr - mtrr_seg->start) >> mtrr_seg->range_shift; |
|
return index; |
|
} |
|
|
|
static u64 fixed_mtrr_range_end_addr(int seg, int index) |
|
{ |
|
struct fixed_mtrr_segment *mtrr_seg = &fixed_seg_table[seg]; |
|
int pos = index - mtrr_seg->range_start; |
|
|
|
return mtrr_seg->start + ((pos + 1) << mtrr_seg->range_shift); |
|
} |
|
|
|
static void var_mtrr_range(struct kvm_mtrr_range *range, u64 *start, u64 *end) |
|
{ |
|
u64 mask; |
|
|
|
*start = range->base & PAGE_MASK; |
|
|
|
mask = range->mask & PAGE_MASK; |
|
|
|
/* This cannot overflow because writing to the reserved bits of |
|
* variable MTRRs causes a #GP. |
|
*/ |
|
*end = (*start | ~mask) + 1; |
|
} |
|
|
|
static void update_mtrr(struct kvm_vcpu *vcpu, u32 msr) |
|
{ |
|
struct kvm_mtrr *mtrr_state = &vcpu->arch.mtrr_state; |
|
gfn_t start, end; |
|
int index; |
|
|
|
if (msr == MSR_IA32_CR_PAT || !tdp_enabled || |
|
!kvm_arch_has_noncoherent_dma(vcpu->kvm)) |
|
return; |
|
|
|
if (!mtrr_is_enabled(mtrr_state) && msr != MSR_MTRRdefType) |
|
return; |
|
|
|
/* fixed MTRRs. */ |
|
if (fixed_msr_to_range(msr, &start, &end)) { |
|
if (!fixed_mtrr_is_enabled(mtrr_state)) |
|
return; |
|
} else if (msr == MSR_MTRRdefType) { |
|
start = 0x0; |
|
end = ~0ULL; |
|
} else { |
|
/* variable range MTRRs. */ |
|
index = (msr - 0x200) / 2; |
|
var_mtrr_range(&mtrr_state->var_ranges[index], &start, &end); |
|
} |
|
|
|
kvm_zap_gfn_range(vcpu->kvm, gpa_to_gfn(start), gpa_to_gfn(end)); |
|
} |
|
|
|
static bool var_mtrr_range_is_valid(struct kvm_mtrr_range *range) |
|
{ |
|
return (range->mask & (1 << 11)) != 0; |
|
} |
|
|
|
static void set_var_mtrr_msr(struct kvm_vcpu *vcpu, u32 msr, u64 data) |
|
{ |
|
struct kvm_mtrr *mtrr_state = &vcpu->arch.mtrr_state; |
|
struct kvm_mtrr_range *tmp, *cur; |
|
int index, is_mtrr_mask; |
|
|
|
index = (msr - 0x200) / 2; |
|
is_mtrr_mask = msr - 0x200 - 2 * index; |
|
cur = &mtrr_state->var_ranges[index]; |
|
|
|
/* remove the entry if it's in the list. */ |
|
if (var_mtrr_range_is_valid(cur)) |
|
list_del(&mtrr_state->var_ranges[index].node); |
|
|
|
/* |
|
* Set all illegal GPA bits in the mask, since those bits must |
|
* implicitly be 0. The bits are then cleared when reading them. |
|
*/ |
|
if (!is_mtrr_mask) |
|
cur->base = data; |
|
else |
|
cur->mask = data | kvm_vcpu_reserved_gpa_bits_raw(vcpu); |
|
|
|
/* add it to the list if it's enabled. */ |
|
if (var_mtrr_range_is_valid(cur)) { |
|
list_for_each_entry(tmp, &mtrr_state->head, node) |
|
if (cur->base >= tmp->base) |
|
break; |
|
list_add_tail(&cur->node, &tmp->node); |
|
} |
|
} |
|
|
|
int kvm_mtrr_set_msr(struct kvm_vcpu *vcpu, u32 msr, u64 data) |
|
{ |
|
int index; |
|
|
|
if (!kvm_mtrr_valid(vcpu, msr, data)) |
|
return 1; |
|
|
|
index = fixed_msr_to_range_index(msr); |
|
if (index >= 0) |
|
*(u64 *)&vcpu->arch.mtrr_state.fixed_ranges[index] = data; |
|
else if (msr == MSR_MTRRdefType) |
|
vcpu->arch.mtrr_state.deftype = data; |
|
else if (msr == MSR_IA32_CR_PAT) |
|
vcpu->arch.pat = data; |
|
else |
|
set_var_mtrr_msr(vcpu, msr, data); |
|
|
|
update_mtrr(vcpu, msr); |
|
return 0; |
|
} |
|
|
|
int kvm_mtrr_get_msr(struct kvm_vcpu *vcpu, u32 msr, u64 *pdata) |
|
{ |
|
int index; |
|
|
|
/* MSR_MTRRcap is a readonly MSR. */ |
|
if (msr == MSR_MTRRcap) { |
|
/* |
|
* SMRR = 0 |
|
* WC = 1 |
|
* FIX = 1 |
|
* VCNT = KVM_NR_VAR_MTRR |
|
*/ |
|
*pdata = 0x500 | KVM_NR_VAR_MTRR; |
|
return 0; |
|
} |
|
|
|
if (!msr_mtrr_valid(msr)) |
|
return 1; |
|
|
|
index = fixed_msr_to_range_index(msr); |
|
if (index >= 0) |
|
*pdata = *(u64 *)&vcpu->arch.mtrr_state.fixed_ranges[index]; |
|
else if (msr == MSR_MTRRdefType) |
|
*pdata = vcpu->arch.mtrr_state.deftype; |
|
else if (msr == MSR_IA32_CR_PAT) |
|
*pdata = vcpu->arch.pat; |
|
else { /* Variable MTRRs */ |
|
int is_mtrr_mask; |
|
|
|
index = (msr - 0x200) / 2; |
|
is_mtrr_mask = msr - 0x200 - 2 * index; |
|
if (!is_mtrr_mask) |
|
*pdata = vcpu->arch.mtrr_state.var_ranges[index].base; |
|
else |
|
*pdata = vcpu->arch.mtrr_state.var_ranges[index].mask; |
|
|
|
*pdata &= ~kvm_vcpu_reserved_gpa_bits_raw(vcpu); |
|
} |
|
|
|
return 0; |
|
} |
|
|
|
void kvm_vcpu_mtrr_init(struct kvm_vcpu *vcpu) |
|
{ |
|
INIT_LIST_HEAD(&vcpu->arch.mtrr_state.head); |
|
} |
|
|
|
struct mtrr_iter { |
|
/* input fields. */ |
|
struct kvm_mtrr *mtrr_state; |
|
u64 start; |
|
u64 end; |
|
|
|
/* output fields. */ |
|
int mem_type; |
|
/* mtrr is completely disabled? */ |
|
bool mtrr_disabled; |
|
/* [start, end) is not fully covered in MTRRs? */ |
|
bool partial_map; |
|
|
|
/* private fields. */ |
|
union { |
|
/* used for fixed MTRRs. */ |
|
struct { |
|
int index; |
|
int seg; |
|
}; |
|
|
|
/* used for var MTRRs. */ |
|
struct { |
|
struct kvm_mtrr_range *range; |
|
/* max address has been covered in var MTRRs. */ |
|
u64 start_max; |
|
}; |
|
}; |
|
|
|
bool fixed; |
|
}; |
|
|
|
static bool mtrr_lookup_fixed_start(struct mtrr_iter *iter) |
|
{ |
|
int seg, index; |
|
|
|
if (!fixed_mtrr_is_enabled(iter->mtrr_state)) |
|
return false; |
|
|
|
seg = fixed_mtrr_addr_to_seg(iter->start); |
|
if (seg < 0) |
|
return false; |
|
|
|
iter->fixed = true; |
|
index = fixed_mtrr_addr_seg_to_range_index(iter->start, seg); |
|
iter->index = index; |
|
iter->seg = seg; |
|
return true; |
|
} |
|
|
|
static bool match_var_range(struct mtrr_iter *iter, |
|
struct kvm_mtrr_range *range) |
|
{ |
|
u64 start, end; |
|
|
|
var_mtrr_range(range, &start, &end); |
|
if (!(start >= iter->end || end <= iter->start)) { |
|
iter->range = range; |
|
|
|
/* |
|
* the function is called when we do kvm_mtrr.head walking. |
|
* Range has the minimum base address which interleaves |
|
* [looker->start_max, looker->end). |
|
*/ |
|
iter->partial_map |= iter->start_max < start; |
|
|
|
/* update the max address has been covered. */ |
|
iter->start_max = max(iter->start_max, end); |
|
return true; |
|
} |
|
|
|
return false; |
|
} |
|
|
|
static void __mtrr_lookup_var_next(struct mtrr_iter *iter) |
|
{ |
|
struct kvm_mtrr *mtrr_state = iter->mtrr_state; |
|
|
|
list_for_each_entry_continue(iter->range, &mtrr_state->head, node) |
|
if (match_var_range(iter, iter->range)) |
|
return; |
|
|
|
iter->range = NULL; |
|
iter->partial_map |= iter->start_max < iter->end; |
|
} |
|
|
|
static void mtrr_lookup_var_start(struct mtrr_iter *iter) |
|
{ |
|
struct kvm_mtrr *mtrr_state = iter->mtrr_state; |
|
|
|
iter->fixed = false; |
|
iter->start_max = iter->start; |
|
iter->range = NULL; |
|
iter->range = list_prepare_entry(iter->range, &mtrr_state->head, node); |
|
|
|
__mtrr_lookup_var_next(iter); |
|
} |
|
|
|
static void mtrr_lookup_fixed_next(struct mtrr_iter *iter) |
|
{ |
|
/* terminate the lookup. */ |
|
if (fixed_mtrr_range_end_addr(iter->seg, iter->index) >= iter->end) { |
|
iter->fixed = false; |
|
iter->range = NULL; |
|
return; |
|
} |
|
|
|
iter->index++; |
|
|
|
/* have looked up for all fixed MTRRs. */ |
|
if (iter->index >= ARRAY_SIZE(iter->mtrr_state->fixed_ranges)) |
|
return mtrr_lookup_var_start(iter); |
|
|
|
/* switch to next segment. */ |
|
if (iter->index > fixed_mtrr_seg_end_range_index(iter->seg)) |
|
iter->seg++; |
|
} |
|
|
|
static void mtrr_lookup_var_next(struct mtrr_iter *iter) |
|
{ |
|
__mtrr_lookup_var_next(iter); |
|
} |
|
|
|
static void mtrr_lookup_start(struct mtrr_iter *iter) |
|
{ |
|
if (!mtrr_is_enabled(iter->mtrr_state)) { |
|
iter->mtrr_disabled = true; |
|
return; |
|
} |
|
|
|
if (!mtrr_lookup_fixed_start(iter)) |
|
mtrr_lookup_var_start(iter); |
|
} |
|
|
|
static void mtrr_lookup_init(struct mtrr_iter *iter, |
|
struct kvm_mtrr *mtrr_state, u64 start, u64 end) |
|
{ |
|
iter->mtrr_state = mtrr_state; |
|
iter->start = start; |
|
iter->end = end; |
|
iter->mtrr_disabled = false; |
|
iter->partial_map = false; |
|
iter->fixed = false; |
|
iter->range = NULL; |
|
|
|
mtrr_lookup_start(iter); |
|
} |
|
|
|
static bool mtrr_lookup_okay(struct mtrr_iter *iter) |
|
{ |
|
if (iter->fixed) { |
|
iter->mem_type = iter->mtrr_state->fixed_ranges[iter->index]; |
|
return true; |
|
} |
|
|
|
if (iter->range) { |
|
iter->mem_type = iter->range->base & 0xff; |
|
return true; |
|
} |
|
|
|
return false; |
|
} |
|
|
|
static void mtrr_lookup_next(struct mtrr_iter *iter) |
|
{ |
|
if (iter->fixed) |
|
mtrr_lookup_fixed_next(iter); |
|
else |
|
mtrr_lookup_var_next(iter); |
|
} |
|
|
|
#define mtrr_for_each_mem_type(_iter_, _mtrr_, _gpa_start_, _gpa_end_) \ |
|
for (mtrr_lookup_init(_iter_, _mtrr_, _gpa_start_, _gpa_end_); \ |
|
mtrr_lookup_okay(_iter_); mtrr_lookup_next(_iter_)) |
|
|
|
u8 kvm_mtrr_get_guest_memory_type(struct kvm_vcpu *vcpu, gfn_t gfn) |
|
{ |
|
struct kvm_mtrr *mtrr_state = &vcpu->arch.mtrr_state; |
|
struct mtrr_iter iter; |
|
u64 start, end; |
|
int type = -1; |
|
const int wt_wb_mask = (1 << MTRR_TYPE_WRBACK) |
|
| (1 << MTRR_TYPE_WRTHROUGH); |
|
|
|
start = gfn_to_gpa(gfn); |
|
end = start + PAGE_SIZE; |
|
|
|
mtrr_for_each_mem_type(&iter, mtrr_state, start, end) { |
|
int curr_type = iter.mem_type; |
|
|
|
/* |
|
* Please refer to Intel SDM Volume 3: 11.11.4.1 MTRR |
|
* Precedences. |
|
*/ |
|
|
|
if (type == -1) { |
|
type = curr_type; |
|
continue; |
|
} |
|
|
|
/* |
|
* If two or more variable memory ranges match and the |
|
* memory types are identical, then that memory type is |
|
* used. |
|
*/ |
|
if (type == curr_type) |
|
continue; |
|
|
|
/* |
|
* If two or more variable memory ranges match and one of |
|
* the memory types is UC, the UC memory type used. |
|
*/ |
|
if (curr_type == MTRR_TYPE_UNCACHABLE) |
|
return MTRR_TYPE_UNCACHABLE; |
|
|
|
/* |
|
* If two or more variable memory ranges match and the |
|
* memory types are WT and WB, the WT memory type is used. |
|
*/ |
|
if (((1 << type) & wt_wb_mask) && |
|
((1 << curr_type) & wt_wb_mask)) { |
|
type = MTRR_TYPE_WRTHROUGH; |
|
continue; |
|
} |
|
|
|
/* |
|
* For overlaps not defined by the above rules, processor |
|
* behavior is undefined. |
|
*/ |
|
|
|
/* We use WB for this undefined behavior. :( */ |
|
return MTRR_TYPE_WRBACK; |
|
} |
|
|
|
if (iter.mtrr_disabled) |
|
return mtrr_disabled_type(vcpu); |
|
|
|
/* not contained in any MTRRs. */ |
|
if (type == -1) |
|
return mtrr_default_type(mtrr_state); |
|
|
|
/* |
|
* We just check one page, partially covered by MTRRs is |
|
* impossible. |
|
*/ |
|
WARN_ON(iter.partial_map); |
|
|
|
return type; |
|
} |
|
EXPORT_SYMBOL_GPL(kvm_mtrr_get_guest_memory_type); |
|
|
|
bool kvm_mtrr_check_gfn_range_consistency(struct kvm_vcpu *vcpu, gfn_t gfn, |
|
int page_num) |
|
{ |
|
struct kvm_mtrr *mtrr_state = &vcpu->arch.mtrr_state; |
|
struct mtrr_iter iter; |
|
u64 start, end; |
|
int type = -1; |
|
|
|
start = gfn_to_gpa(gfn); |
|
end = gfn_to_gpa(gfn + page_num); |
|
mtrr_for_each_mem_type(&iter, mtrr_state, start, end) { |
|
if (type == -1) { |
|
type = iter.mem_type; |
|
continue; |
|
} |
|
|
|
if (type != iter.mem_type) |
|
return false; |
|
} |
|
|
|
if (iter.mtrr_disabled) |
|
return true; |
|
|
|
if (!iter.partial_map) |
|
return true; |
|
|
|
if (type == -1) |
|
return true; |
|
|
|
return type == mtrr_default_type(mtrr_state); |
|
}
|
|
|