[V8 1/4] x86/xsaves: add basic definitions/helpers to support xsaves

[Shuai Ruan <shuai.ruan@linux.intel.com>]

This patch add basic definitions/helpers which will be used in
later patches.

Signed-off-by: Shuai Ruan <shuai.ruan@linux.intel.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
---
 xen/arch/x86/xstate.c           | 19 +++++++++++++++++++
 xen/include/asm-x86/hvm/vcpu.h  |  1 +
 xen/include/asm-x86/msr-index.h |  2 ++
 xen/include/asm-x86/xstate.h    | 12 ++++++++++--
 4 files changed, 32 insertions(+), 2 deletions(-)

diff --git a/xen/arch/x86/xstate.c b/xen/arch/x86/xstate.c
index 9ddff90..add8c55 100644
--- a/xen/arch/x86/xstate.c
+++ b/xen/arch/x86/xstate.c
@@ -24,6 +24,9 @@ static u32 __read_mostly xsave_cntxt_size;
 /* A 64-bit bitmask of the XSAVE/XRSTOR features supported by processor. */
 u64 __read_mostly xfeature_mask;
 
+/* Cached xss for fast read */
+static DEFINE_PER_CPU(uint64_t, xss);
+
 /* Cached xcr0 for fast read */
 static DEFINE_PER_CPU(uint64_t, xcr0);
 
@@ -60,6 +63,22 @@ uint64_t get_xcr0(void)
     return this_cpu(xcr0);
 }
 
+void set_msr_xss(u64 xss)
+{
+    u64 *this_xss = &this_cpu(xss);
+
+    if ( *this_xss != xss )
+    {
+        wrmsrl(MSR_IA32_XSS, xss);
+        *this_xss = xss;
+    }
+}
+
+uint64_t get_msr_xss(void)
+{
+    return this_cpu(xss);
+}
+
 void xsave(struct vcpu *v, uint64_t mask)
 {
     struct xsave_struct *ptr = v->arch.xsave_area;
diff --git a/xen/include/asm-x86/hvm/vcpu.h b/xen/include/asm-x86/hvm/vcpu.h
index f553814..de81f8a 100644
--- a/xen/include/asm-x86/hvm/vcpu.h
+++ b/xen/include/asm-x86/hvm/vcpu.h
@@ -173,6 +173,7 @@ struct hvm_vcpu {
 
     u32                 msr_tsc_aux;
     u64                 msr_tsc_adjust;
+    u64                 msr_xss;
 
     union {
         struct arch_vmx_struct vmx;
diff --git a/xen/include/asm-x86/msr-index.h b/xen/include/asm-x86/msr-index.h
index 65c1d02..b8ad93c 100644
--- a/xen/include/asm-x86/msr-index.h
+++ b/xen/include/asm-x86/msr-index.h
@@ -58,6 +58,8 @@
 
 #define MSR_IA32_BNDCFGS		0x00000D90
 
+#define MSR_IA32_XSS			0x00000da0
+
 #define MSR_MTRRfix64K_00000		0x00000250
 #define MSR_MTRRfix16K_80000		0x00000258
 #define MSR_MTRRfix16K_A0000		0x00000259
diff --git a/xen/include/asm-x86/xstate.h b/xen/include/asm-x86/xstate.h
index f0d8f0b..b95a5b5 100644
--- a/xen/include/asm-x86/xstate.h
+++ b/xen/include/asm-x86/xstate.h
@@ -19,8 +19,12 @@
 
 #define XCR_XFEATURE_ENABLED_MASK 0x00000000  /* index of XCR0 */
 
+#define XSAVE_HDR_SIZE            64
+#define XSAVE_SSE_OFFSET          160
 #define XSTATE_YMM_SIZE           256
-#define XSTATE_AREA_MIN_SIZE      (512 + 64)  /* FP/SSE + XSAVE.HEADER */
+#define FXSAVE_SIZE               512
+#define XSAVE_HDR_OFFSET          FXSAVE_SIZE
+#define XSTATE_AREA_MIN_SIZE      (FXSAVE_SIZE + XSAVE_HDR_SIZE)
 
 #define XSTATE_FP      (1ULL << 0)
 #define XSTATE_SSE     (1ULL << 1)
@@ -38,6 +42,7 @@
 #define XSTATE_ALL     (~(1ULL << 63))
 #define XSTATE_NONLAZY (XSTATE_LWP | XSTATE_BNDREGS | XSTATE_BNDCSR)
 #define XSTATE_LAZY    (XSTATE_ALL & ~XSTATE_NONLAZY)
+#define XSTATE_COMPACTION_ENABLED  (1ULL << 63)
 
 extern u64 xfeature_mask;
 
@@ -68,7 +73,8 @@ struct __packed __attribute__((aligned (64))) xsave_struct
 
     struct {
         u64 xstate_bv;
-        u64 reserved[7];
+        u64 xcomp_bv;
+        u64 reserved[6];
     } xsave_hdr;                             /* The 64-byte header */
 
     struct { char x[XSTATE_YMM_SIZE]; } ymm; /* YMM */
@@ -78,6 +84,8 @@ struct __packed __attribute__((aligned (64))) xsave_struct
 /* extended state operations */
 bool_t __must_check set_xcr0(u64 xfeatures);
 uint64_t get_xcr0(void);
+void set_msr_xss(u64 xss);
+uint64_t get_msr_xss(void);
 void xsave(struct vcpu *v, uint64_t mask);
 void xrstor(struct vcpu *v, uint64_t mask);
 bool_t xsave_enabled(const struct vcpu *v);
-- 
1.9.1