Skip to content

Commit

Permalink
KVM: VMX: Use kvm_segment to save protected-mode segments when enteri…
Browse files Browse the repository at this point in the history 
…ng realmode

Instead of using struct kvm_save_segment, use struct kvm_segment, which is what
the other APIs use.  This leads to some simplification.

We replace save_rmode_seg() with a call to vmx_save_segment().  Since this depends
on rmode.vm86_active, we move the call to before setting the flag.

Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
  • Loading branch information
Avi Kivity authored and Marcelo Tosatti committed Aug 27, 2012
1 parent 72fbefe commit f5f7b2f
Showing 1 changed file with 24 additions and 61 deletions.
85 changes: 24 additions & 61 deletions arch/x86/kvm/vmx.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -405,16 +405,16 @@ struct vcpu_vmx {
struct {
int vm86_active;
ulong save_rflags;
struct kvm_segment segs[8];
} rmode;
struct {
u32 bitmask; /* 4 bits per segment (1 bit per field) */
struct kvm_save_segment {
u16 selector;
unsigned long base;
u32 limit;
u32 ar;
} tr, es, ds, fs, gs;
} rmode;
struct {
u32 bitmask; /* 4 bits per segment (1 bit per field) */
struct kvm_save_segment seg[8];
} seg[8];
} segment_cache;
int vpid;
bool emulation_required;
Expand Down Expand Up @@ -2693,15 +2693,12 @@ static __exit void hardware_unsetup(void)
free_kvm_area();
}

static void fix_pmode_dataseg(int seg, struct kvm_segment *save)
static void fix_pmode_dataseg(struct kvm_vcpu *vcpu, int seg, struct kvm_segment *save)
{
struct kvm_vmx_segment_field *sf = &kvm_vmx_segment_fields[seg];

if (vmcs_readl(sf->base) == save->base && (save->ar_bytes & AR_S_MASK)) {
vmcs_write16(sf->selector, save->selector);
vmcs_writel(sf->base, save->base);
vmcs_write32(sf->limit, save->limit);
vmcs_write32(sf->ar_bytes, save->ar);
if (vmcs_readl(sf->base) == save->base && save->s) {
vmx_set_segment(vcpu, save, seg);
} else {
u32 dpl = (vmcs_read16(sf->selector) & SELECTOR_RPL_MASK)
<< AR_DPL_SHIFT;
Expand All @@ -2719,10 +2716,7 @@ static void enter_pmode(struct kvm_vcpu *vcpu)

vmx_segment_cache_clear(vmx);

vmcs_write16(GUEST_TR_SELECTOR, vmx->rmode.tr.selector);
vmcs_writel(GUEST_TR_BASE, vmx->rmode.tr.base);
vmcs_write32(GUEST_TR_LIMIT, vmx->rmode.tr.limit);
vmcs_write32(GUEST_TR_AR_BYTES, vmx->rmode.tr.ar);
vmx_set_segment(vcpu, &vmx->rmode.segs[VCPU_SREG_TR], VCPU_SREG_TR);

flags = vmcs_readl(GUEST_RFLAGS);
flags &= RMODE_GUEST_OWNED_EFLAGS_BITS;
Expand All @@ -2737,10 +2731,10 @@ static void enter_pmode(struct kvm_vcpu *vcpu)
if (emulate_invalid_guest_state)
return;

fix_pmode_dataseg(VCPU_SREG_ES, &vmx->rmode.es);
fix_pmode_dataseg(VCPU_SREG_DS, &vmx->rmode.ds);
fix_pmode_dataseg(VCPU_SREG_GS, &vmx->rmode.gs);
fix_pmode_dataseg(VCPU_SREG_FS, &vmx->rmode.fs);
fix_pmode_dataseg(vcpu, VCPU_SREG_ES, &vmx->rmode.segs[VCPU_SREG_ES]);
fix_pmode_dataseg(vcpu, VCPU_SREG_DS, &vmx->rmode.segs[VCPU_SREG_DS]);
fix_pmode_dataseg(vcpu, VCPU_SREG_FS, &vmx->rmode.segs[VCPU_SREG_FS]);
fix_pmode_dataseg(vcpu, VCPU_SREG_GS, &vmx->rmode.segs[VCPU_SREG_GS]);

vmx_segment_cache_clear(vmx);

Expand Down Expand Up @@ -2768,17 +2762,7 @@ static gva_t rmode_tss_base(struct kvm *kvm)
return kvm->arch.tss_addr;
}

static void save_rmode_seg(int seg, struct kvm_save_segment *save)
{
struct kvm_vmx_segment_field *sf = &kvm_vmx_segment_fields[seg];

save->selector = vmcs_read16(sf->selector);
save->base = vmcs_readl(sf->base);
save->limit = vmcs_read32(sf->limit);
save->ar = vmcs_read32(sf->ar_bytes);
}

static void fix_rmode_seg(int seg, struct kvm_save_segment *save)
static void fix_rmode_seg(int seg, struct kvm_segment *save)
{
struct kvm_vmx_segment_field *sf = &kvm_vmx_segment_fields[seg];

Expand All @@ -2801,14 +2785,15 @@ static void enter_rmode(struct kvm_vcpu *vcpu)
if (enable_unrestricted_guest)
return;

vmx_get_segment(vcpu, &vmx->rmode.segs[VCPU_SREG_TR], VCPU_SREG_TR);
vmx_get_segment(vcpu, &vmx->rmode.segs[VCPU_SREG_ES], VCPU_SREG_ES);
vmx_get_segment(vcpu, &vmx->rmode.segs[VCPU_SREG_DS], VCPU_SREG_DS);
vmx_get_segment(vcpu, &vmx->rmode.segs[VCPU_SREG_FS], VCPU_SREG_FS);
vmx_get_segment(vcpu, &vmx->rmode.segs[VCPU_SREG_GS], VCPU_SREG_GS);

vmx->emulation_required = 1;
vmx->rmode.vm86_active = 1;

save_rmode_seg(VCPU_SREG_TR, &vmx->rmode.tr);
save_rmode_seg(VCPU_SREG_ES, &vmx->rmode.es);
save_rmode_seg(VCPU_SREG_DS, &vmx->rmode.ds);
save_rmode_seg(VCPU_SREG_FS, &vmx->rmode.fs);
save_rmode_seg(VCPU_SREG_GS, &vmx->rmode.gs);

/*
* Very old userspace does not call KVM_SET_TSS_ADDR before entering
Expand Down Expand Up @@ -3118,35 +3103,22 @@ static void vmx_get_segment(struct kvm_vcpu *vcpu,
struct kvm_segment *var, int seg)
{
struct vcpu_vmx *vmx = to_vmx(vcpu);
struct kvm_save_segment *save;
u32 ar;

if (vmx->rmode.vm86_active
&& (seg == VCPU_SREG_TR || seg == VCPU_SREG_ES
|| seg == VCPU_SREG_DS || seg == VCPU_SREG_FS
|| seg == VCPU_SREG_GS)
&& !emulate_invalid_guest_state) {
switch (seg) {
case VCPU_SREG_TR: save = &vmx->rmode.tr; break;
case VCPU_SREG_ES: save = &vmx->rmode.es; break;
case VCPU_SREG_DS: save = &vmx->rmode.ds; break;
case VCPU_SREG_FS: save = &vmx->rmode.fs; break;
case VCPU_SREG_GS: save = &vmx->rmode.gs; break;
default: BUG();
}
var->selector = save->selector;
var->base = save->base;
var->limit = save->limit;
ar = save->ar;
*var = vmx->rmode.segs[seg];
if (seg == VCPU_SREG_TR
|| var->selector == vmx_read_guest_seg_selector(vmx, seg))
goto use_saved_rmode_seg;
return;
}
var->base = vmx_read_guest_seg_base(vmx, seg);
var->limit = vmx_read_guest_seg_limit(vmx, seg);
var->selector = vmx_read_guest_seg_selector(vmx, seg);
ar = vmx_read_guest_seg_ar(vmx, seg);
use_saved_rmode_seg:
if ((ar & AR_UNUSABLE_MASK) && !emulate_invalid_guest_state)
ar = 0;
var->type = ar & 15;
Expand Down Expand Up @@ -3235,10 +3207,7 @@ static void vmx_set_segment(struct kvm_vcpu *vcpu,

if (vmx->rmode.vm86_active && seg == VCPU_SREG_TR) {
vmcs_write16(sf->selector, var->selector);
vmx->rmode.tr.selector = var->selector;
vmx->rmode.tr.base = var->base;
vmx->rmode.tr.limit = var->limit;
vmx->rmode.tr.ar = vmx_segment_access_rights(var);
vmx->rmode.segs[VCPU_SREG_TR] = *var;
return;
}
vmcs_writel(sf->base, var->base);
Expand Down Expand Up @@ -3289,16 +3258,10 @@ static void vmx_set_segment(struct kvm_vcpu *vcpu,
vmcs_readl(GUEST_CS_BASE) >> 4);
break;
case VCPU_SREG_ES:
fix_rmode_seg(VCPU_SREG_ES, &vmx->rmode.es);
break;
case VCPU_SREG_DS:
fix_rmode_seg(VCPU_SREG_DS, &vmx->rmode.ds);
break;
case VCPU_SREG_GS:
fix_rmode_seg(VCPU_SREG_GS, &vmx->rmode.gs);
break;
case VCPU_SREG_FS:
fix_rmode_seg(VCPU_SREG_FS, &vmx->rmode.fs);
fix_rmode_seg(seg, &vmx->rmode.segs[seg]);
break;
case VCPU_SREG_SS:
vmcs_write16(GUEST_SS_SELECTOR,
Expand Down

0 comments on commit f5f7b2f

Please sign in to comment.