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Message-Id: <20061112145545.2497FA0001@cleopatra.q>
Date: Sun, 12 Nov 2006 14:55:44 -0000
From: Avi Kivity <avi@...ranet.com>
To: kvm-devel@...ts.sourceforge.net
Cc: akpm@...l.org, linux-kernel@...r.kernel.org
Subject: [PATCH] KVM: Segment access cleanup
Instead of using pasting macros, put the vmx segment field indices into
an array and use the array to access the fields indirectly. Cleaner code
as well as ~200 bytes saved.
Signed-off-by: Avi Kivity <avi@...ranet.com>
Index: linux-2.6/drivers/kvm/kvm.h
===================================================================
--- linux-2.6.orig/drivers/kvm/kvm.h
+++ linux-2.6/drivers/kvm/kvm.h
@@ -195,10 +195,10 @@ struct kvm_vcpu {
unsigned char mmio_data[8];
gpa_t mmio_phys_addr;
- struct{
+ struct {
int active;
u8 save_iopl;
- struct {
+ struct kvm_save_segment {
u16 selector;
unsigned long base;
u32 limit;
Index: linux-2.6/drivers/kvm/kvm_main.c
===================================================================
--- linux-2.6.orig/drivers/kvm/kvm_main.c
+++ linux-2.6/drivers/kvm/kvm_main.c
@@ -62,6 +62,41 @@ static struct kvm_stats_debugfs_item {
static struct dentry *debugfs_dir;
+enum {
+ VCPU_SREG_CS,
+ VCPU_SREG_DS,
+ VCPU_SREG_ES,
+ VCPU_SREG_FS,
+ VCPU_SREG_GS,
+ VCPU_SREG_SS,
+ VCPU_SREG_TR,
+ VCPU_SREG_LDTR,
+};
+
+#define VMX_SEGMENT_FIELD(seg) \
+ [VCPU_SREG_##seg] { \
+ GUEST_##seg##_SELECTOR, \
+ GUEST_##seg##_BASE, \
+ GUEST_##seg##_LIMIT, \
+ GUEST_##seg##_AR_BYTES, \
+ }
+
+static struct kvm_vmx_segment_field {
+ unsigned selector;
+ unsigned base;
+ unsigned limit;
+ unsigned ar_bytes;
+} kvm_vmx_segment_fields[] = {
+ VMX_SEGMENT_FIELD(CS),
+ VMX_SEGMENT_FIELD(DS),
+ VMX_SEGMENT_FIELD(ES),
+ VMX_SEGMENT_FIELD(FS),
+ VMX_SEGMENT_FIELD(GS),
+ VMX_SEGMENT_FIELD(SS),
+ VMX_SEGMENT_FIELD(TR),
+ VMX_SEGMENT_FIELD(LDTR),
+};
+
static const u32 vmx_msr_index[] = {
#ifdef __x86_64__
MSR_SYSCALL_MASK, MSR_LSTAR, MSR_CSTAR, MSR_KERNEL_GS_BASE,
@@ -689,6 +724,22 @@ static void update_exception_bitmap(stru
vmcs_write32(EXCEPTION_BITMAP, 1 << PF_VECTOR);
}
+static void fix_pmode_dataseg(int seg, struct kvm_save_segment *save)
+{
+ struct kvm_vmx_segment_field *sf = &kvm_vmx_segment_fields[seg];
+
+ if (vmcs_readl(sf->base) == save->base) {
+ 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);
+ } else {
+ u32 dpl = (vmcs_read16(sf->selector) & SELECTOR_RPL_MASK)
+ << AR_DPL_SHIFT;
+ vmcs_write32(sf->ar_bytes, 0x93 | dpl);
+ }
+}
+
static void enter_pmode(struct kvm_vcpu *vcpu)
{
unsigned long flags;
@@ -709,24 +760,10 @@ static void enter_pmode(struct kvm_vcpu
update_exception_bitmap(vcpu);
- #define FIX_PMODE_DATASEG(seg, save) { \
- if (vmcs_readl(GUEST_##seg##_BASE) == save.base) { \
- vmcs_write16(GUEST_##seg##_SELECTOR, save.selector); \
- vmcs_writel(GUEST_##seg##_BASE, save.base); \
- vmcs_write32(GUEST_##seg##_LIMIT, save.limit); \
- vmcs_write32(GUEST_##seg##_AR_BYTES, save.ar); \
- } else { \
- u32 dpl = (vmcs_read16(GUEST_##seg##_SELECTOR) & \
- SELECTOR_RPL_MASK) << AR_DPL_SHIFT; \
- vmcs_write32(GUEST_##seg##_AR_BYTES, 0x93 | dpl); \
- } \
- }
-
- FIX_PMODE_DATASEG(ES, vcpu->rmode.es);
- FIX_PMODE_DATASEG(DS, vcpu->rmode.ds);
- FIX_PMODE_DATASEG(GS, vcpu->rmode.gs);
- FIX_PMODE_DATASEG(FS, vcpu->rmode.fs);
-
+ fix_pmode_dataseg(VCPU_SREG_ES, &vcpu->rmode.es);
+ fix_pmode_dataseg(VCPU_SREG_DS, &vcpu->rmode.ds);
+ fix_pmode_dataseg(VCPU_SREG_GS, &vcpu->rmode.gs);
+ fix_pmode_dataseg(VCPU_SREG_FS, &vcpu->rmode.fs);
vmcs_write16(GUEST_SS_SELECTOR, 0);
vmcs_write32(GUEST_SS_AR_BYTES, 0x93);
@@ -742,6 +779,19 @@ static int rmode_tss_base(struct kvm* kv
return base_gfn << PAGE_SHIFT;
}
+static void fix_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);
+ vmcs_write16(sf->selector, vmcs_readl(sf->base) >> 4);
+ vmcs_write32(sf->limit, 0xffff);
+ vmcs_write32(sf->ar_bytes, 0xf3);
+}
+
static void enter_rmode(struct kvm_vcpu *vcpu)
{
unsigned long flags;
@@ -766,17 +816,6 @@ static void enter_rmode(struct kvm_vcpu
vmcs_writel(GUEST_CR4, vmcs_readl(GUEST_CR4) | CR4_VME_MASK);
update_exception_bitmap(vcpu);
- #define FIX_RMODE_SEG(seg, save) { \
- save.selector = vmcs_read16(GUEST_##seg##_SELECTOR); \
- save.base = vmcs_readl(GUEST_##seg##_BASE); \
- save.limit = vmcs_read32(GUEST_##seg##_LIMIT); \
- save.ar = vmcs_read32(GUEST_##seg##_AR_BYTES); \
- vmcs_write16(GUEST_##seg##_SELECTOR, \
- vmcs_readl(GUEST_##seg##_BASE) >> 4); \
- vmcs_write32(GUEST_##seg##_LIMIT, 0xffff); \
- vmcs_write32(GUEST_##seg##_AR_BYTES, 0xf3); \
- }
-
vmcs_write16(GUEST_SS_SELECTOR, vmcs_readl(GUEST_SS_BASE) >> 4);
vmcs_write32(GUEST_SS_LIMIT, 0xffff);
vmcs_write32(GUEST_SS_AR_BYTES, 0xf3);
@@ -784,10 +823,10 @@ static void enter_rmode(struct kvm_vcpu
vmcs_write32(GUEST_CS_AR_BYTES, 0xf3);
vmcs_write16(GUEST_CS_SELECTOR, vmcs_readl(GUEST_CS_BASE) >> 4);
- FIX_RMODE_SEG(ES, vcpu->rmode.es);
- FIX_RMODE_SEG(DS, vcpu->rmode.ds);
- FIX_RMODE_SEG(GS, vcpu->rmode.gs);
- FIX_RMODE_SEG(FS, vcpu->rmode.fs);
+ fix_rmode_seg(VCPU_SREG_ES, &vcpu->rmode.es);
+ fix_rmode_seg(VCPU_SREG_DS, &vcpu->rmode.ds);
+ fix_rmode_seg(VCPU_SREG_GS, &vcpu->rmode.gs);
+ fix_rmode_seg(VCPU_SREG_FS, &vcpu->rmode.fs);
}
static int init_rmode_tss(struct kvm* kvm)
@@ -1116,6 +1155,16 @@ static void vmcs_write32_fixedbits(u32 m
vmcs_write32(vmcs_field, val);
}
+static void seg_setup(int seg)
+{
+ struct kvm_vmx_segment_field *sf = &kvm_vmx_segment_fields[seg];
+
+ vmcs_write16(sf->selector, 0);
+ vmcs_writel(sf->base, 0);
+ vmcs_write32(sf->limit, 0xffff);
+ vmcs_write32(sf->ar_bytes, 0x93);
+}
+
/*
* Sets up the vmcs for emulated real mode.
*/
@@ -1146,13 +1195,6 @@ static int kvm_vcpu_setup(struct kvm_vcp
fx_init(vcpu);
-#define SEG_SETUP(seg) do { \
- vmcs_write16(GUEST_##seg##_SELECTOR, 0); \
- vmcs_writel(GUEST_##seg##_BASE, 0); \
- vmcs_write32(GUEST_##seg##_LIMIT, 0xffff); \
- vmcs_write32(GUEST_##seg##_AR_BYTES, 0x93); \
- } while (0)
-
/*
* GUEST_CS_BASE should really be 0xffff0000, but VT vm86 mode
* insists on having GUEST_CS_BASE == GUEST_CS_SELECTOR << 4. Sigh.
@@ -1162,11 +1204,11 @@ static int kvm_vcpu_setup(struct kvm_vcp
vmcs_write32(GUEST_CS_LIMIT, 0xffff);
vmcs_write32(GUEST_CS_AR_BYTES, 0x9b);
- SEG_SETUP(DS);
- SEG_SETUP(ES);
- SEG_SETUP(FS);
- SEG_SETUP(GS);
- SEG_SETUP(SS);
+ seg_setup(VCPU_SREG_DS);
+ seg_setup(VCPU_SREG_ES);
+ seg_setup(VCPU_SREG_FS);
+ seg_setup(VCPU_SREG_GS);
+ seg_setup(VCPU_SREG_SS);
vmcs_write16(GUEST_TR_SELECTOR, 0);
vmcs_writel(GUEST_TR_BASE, 0);
@@ -2900,6 +2942,28 @@ static int kvm_dev_ioctl_set_regs(struct
return 0;
}
+static void get_segment(struct kvm_segment *var, int seg)
+{
+ struct kvm_vmx_segment_field *sf = &kvm_vmx_segment_fields[seg];
+ u32 ar;
+
+ var->base = vmcs_readl(sf->base);
+ var->limit = vmcs_read32(sf->limit);
+ var->selector = vmcs_read16(sf->selector);
+ ar = vmcs_read32(sf->ar_bytes);
+ if (ar & AR_UNUSABLE_MASK)
+ ar = 0;
+ var->type = ar & 15;
+ var->s = (ar >> 4) & 1;
+ var->dpl = (ar >> 5) & 3;
+ var->present = (ar >> 7) & 1;
+ var->avl = (ar >> 12) & 1;
+ var->l = (ar >> 13) & 1;
+ var->db = (ar >> 14) & 1;
+ var->g = (ar >> 15) & 1;
+ var->unusable = (ar >> 16) & 1;
+}
+
static int kvm_dev_ioctl_get_sregs(struct kvm *kvm, struct kvm_sregs *sregs)
{
struct kvm_vcpu *vcpu;
@@ -2910,36 +2974,15 @@ static int kvm_dev_ioctl_get_sregs(struc
if (!vcpu)
return -ENOENT;
-#define get_segment(var, seg) \
- do { \
- u32 ar; \
- \
- sregs->var.base = vmcs_readl(GUEST_##seg##_BASE); \
- sregs->var.limit = vmcs_read32(GUEST_##seg##_LIMIT); \
- sregs->var.selector = vmcs_read16(GUEST_##seg##_SELECTOR); \
- ar = vmcs_read32(GUEST_##seg##_AR_BYTES); \
- if (ar & AR_UNUSABLE_MASK) ar = 0; \
- sregs->var.type = ar & 15; \
- sregs->var.s = (ar >> 4) & 1; \
- sregs->var.dpl = (ar >> 5) & 3; \
- sregs->var.present = (ar >> 7) & 1; \
- sregs->var.avl = (ar >> 12) & 1; \
- sregs->var.l = (ar >> 13) & 1; \
- sregs->var.db = (ar >> 14) & 1; \
- sregs->var.g = (ar >> 15) & 1; \
- sregs->var.unusable = (ar >> 16) & 1; \
- } while (0);
-
- get_segment(cs, CS);
- get_segment(ds, DS);
- get_segment(es, ES);
- get_segment(fs, FS);
- get_segment(gs, GS);
- get_segment(ss, SS);
-
- get_segment(tr, TR);
- get_segment(ldt, LDTR);
-#undef get_segment
+ get_segment(&sregs->cs, VCPU_SREG_CS);
+ get_segment(&sregs->ds, VCPU_SREG_DS);
+ get_segment(&sregs->es, VCPU_SREG_ES);
+ get_segment(&sregs->fs, VCPU_SREG_FS);
+ get_segment(&sregs->gs, VCPU_SREG_GS);
+ get_segment(&sregs->ss, VCPU_SREG_SS);
+
+ get_segment(&sregs->tr, VCPU_SREG_TR);
+ get_segment(&sregs->ldt, VCPU_SREG_LDTR);
#define get_dtable(var, table) \
sregs->var.limit = vmcs_read32(GUEST_##table##_LIMIT), \
@@ -2964,6 +3007,29 @@ static int kvm_dev_ioctl_get_sregs(struc
return 0;
}
+static void set_segment(struct kvm_segment *var, int seg)
+{
+ struct kvm_vmx_segment_field *sf = &kvm_vmx_segment_fields[seg];
+ u32 ar;
+
+ vmcs_writel(sf->base, var->base);
+ vmcs_write32(sf->limit, var->limit);
+ vmcs_write16(sf->selector, var->selector);
+ if (var->unusable)
+ ar = 1 << 16;
+ else {
+ ar = var->type & 15;
+ ar |= (var->s & 1) << 4;
+ ar |= (var->dpl & 3) << 5;
+ ar |= (var->present & 1) << 7;
+ ar |= (var->avl & 1) << 12;
+ ar |= (var->l & 1) << 13;
+ ar |= (var->db & 1) << 14;
+ ar |= (var->g & 1) << 15;
+ }
+ vmcs_write32(sf->ar_bytes, ar);
+}
+
static int kvm_dev_ioctl_set_sregs(struct kvm *kvm, struct kvm_sregs *sregs)
{
struct kvm_vcpu *vcpu;
@@ -2975,39 +3041,15 @@ static int kvm_dev_ioctl_set_sregs(struc
if (!vcpu)
return -ENOENT;
-#define set_segment(var, seg) \
- do { \
- u32 ar; \
- \
- vmcs_writel(GUEST_##seg##_BASE, sregs->var.base); \
- vmcs_write32(GUEST_##seg##_LIMIT, sregs->var.limit); \
- vmcs_write16(GUEST_##seg##_SELECTOR, sregs->var.selector); \
- if (sregs->var.unusable) { \
- ar = (1 << 16); \
- } else { \
- ar = (sregs->var.type & 15); \
- ar |= (sregs->var.s & 1) << 4; \
- ar |= (sregs->var.dpl & 3) << 5; \
- ar |= (sregs->var.present & 1) << 7; \
- ar |= (sregs->var.avl & 1) << 12; \
- ar |= (sregs->var.l & 1) << 13; \
- ar |= (sregs->var.db & 1) << 14; \
- ar |= (sregs->var.g & 1) << 15; \
- } \
- vmcs_write32(GUEST_##seg##_AR_BYTES, ar); \
- } while (0);
-
- set_segment(cs, CS);
- set_segment(ds, DS);
- set_segment(es, ES);
- set_segment(fs, FS);
- set_segment(gs, GS);
- set_segment(ss, SS);
-
- set_segment(tr, TR);
+ set_segment(&sregs->cs, VCPU_SREG_CS);
+ set_segment(&sregs->ds, VCPU_SREG_DS);
+ set_segment(&sregs->es, VCPU_SREG_ES);
+ set_segment(&sregs->fs, VCPU_SREG_FS);
+ set_segment(&sregs->gs, VCPU_SREG_GS);
+ set_segment(&sregs->ss, VCPU_SREG_SS);
- set_segment(ldt, LDTR);
-#undef set_segment
+ set_segment(&sregs->tr, VCPU_SREG_TR);
+ set_segment(&sregs->ldt, VCPU_SREG_LDTR);
#define set_dtable(var, table) \
vmcs_write32(GUEST_##table##_LIMIT, sregs->var.limit), \
-
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