Commit f5f7b2fe authored by Avi Kivity's avatar Avi Kivity Committed by Marcelo Tosatti
Browse files

KVM: VMX: Use kvm_segment to save protected-mode segments when entering 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: default avatarAvi Kivity <avi@redhat.com>
Signed-off-by: default avatarMarcelo Tosatti <mtosatti@redhat.com>
parent 72fbefec

arch/x86/kvm/vmx.c

+24 −61
Original line number Diff line number Diff line
@@ -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;
@@ -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;
@@ -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;
@@ -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);
@@ -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];
@@ -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
@@ -3118,7 +3103,6 @@ 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
@@ -3126,27 +3110,15 @@ static void vmx_get_segment(struct kvm_vcpu *vcpu, 
		|| 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;
@@ -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);
@@ -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,

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