diff mbox series

[3/4] Add hepler functions for CPUID xsave area size calculation.

Message ID 7a6de6a8c37161fc207f7003fc0e762045fb4028.1545806972.git.weijiang.yang@intel.com (mailing list archive)
State New, archived
Headers show
Series This patch-set is to enable Guest CET support. | expand

Commit Message

Yang, Weijiang Dec. 26, 2018, 8:25 a.m. UTC 
These functions are called when return CPUID xsave area
size information.

Signed-off-by: Zhang Yi <yi.z.zhang@linux.intel.com>
Signed-off-by: Yang Weijiang <weijiang.yang@intel.com>
---
 target/i386/cpu.c | 26 +++++++++++++++++++++++++-
 1 file changed, 25 insertions(+), 1 deletion(-)

Comments

Christophe de Dinechin Jan. 8, 2019, 4:11 p.m. UTC | #1 
Typo in subject line (helper)

> On 26 Dec 2018, at 09:25, Yang Weijiang <weijiang.yang@intel.com> wrote:
> 
> These functions are called when return CPUID xsave area
> size information.
> 
> Signed-off-by: Zhang Yi <yi.z.zhang@linux.intel.com>
> Signed-off-by: Yang Weijiang <weijiang.yang@intel.com>
> ---
> target/i386/cpu.c | 26 +++++++++++++++++++++++++-
> 1 file changed, 25 insertions(+), 1 deletion(-)
> 
> diff --git a/target/i386/cpu.c b/target/i386/cpu.c
> index 3630c688d6..cf4f2798dc 100644
> --- a/target/i386/cpu.c
> +++ b/target/i386/cpu.c
> @@ -1281,12 +1281,34 @@ static inline bool accel_uses_host_cpuid(void)
>     return kvm_enabled() || hvf_enabled();
> }
> 
> +static uint32_t xsave_area_size_compat(uint64_t mask)

Just curious, why “compat”?

> +{
> +    int i;
> +    uint64_t ret = 0;
> +    uint32_t offset;
> +
> +    for (i = 0; i < ARRAY_SIZE(x86_ext_save_areas); i++) {
> +        const ExtSaveArea *esa = &x86_ext_save_areas[i];
> +        offset = i > 1 ? ret : esa->offset;

What about a named constant instead of ‘1’?

(note that a loop around line 4657 starts at 2, so I guess it’s OK to use 1 here, or at least >= 2 ;-)


> +        if ((mask >> i) & 1) {
> +            ret = MAX(ret, offset + esa->size);
> +        }
> +    }
> +    return ret;
> +}
> +
> static inline uint64_t x86_cpu_xsave_components(X86CPU *cpu)
> {
>     return ((uint64_t)cpu->env.features[FEAT_XSAVE_COMP_HI]) << 32 |
>            cpu->env.features[FEAT_XSAVE_COMP_LO];
> }
> 
> +static inline uint64_t x86_cpu_xsave_sv_components(X86CPU *cpu)
> +{
> +    return ((uint64_t)cpu->env.features[FEAT_XSAVE_SV_HI]) << 32 |
> +           cpu->env.features[FEAT_XSAVE_SV_LO];
> +}
> +
> const char *get_register_name_32(unsigned int reg)
> {
>     if (reg >= CPU_NB_REGS32) {
> @@ -4913,8 +4935,10 @@ static void x86_cpu_enable_xsave_components(X86CPU *cpu)
>         }
>     }
> 
> -    env->features[FEAT_XSAVE_COMP_LO] = mask;
> +    env->features[FEAT_XSAVE_COMP_LO] = mask & CPUID_XSTATE_USER_MASK;
>     env->features[FEAT_XSAVE_COMP_HI] = mask >> 32;
> +    env->features[FEAT_XSAVE_SV_LO] = mask & CPUID_XSTATE_KERNEL_MASK;
> +    env->features[FEAT_XSAVE_SV_HI] = mask >> 32;
> }
> 
> /***** Steps involved on loading and filtering CPUID data
> -- 
> 2.17.1
>
diff mbox series

Patch

diff --git a/target/i386/cpu.c b/target/i386/cpu.c
index 3630c688d6..cf4f2798dc 100644
--- a/target/i386/cpu.c
+++ b/target/i386/cpu.c
@@ -1281,12 +1281,34 @@  static inline bool accel_uses_host_cpuid(void)
     return kvm_enabled() || hvf_enabled();
 }
 
+static uint32_t xsave_area_size_compat(uint64_t mask)
+{
+    int i;
+    uint64_t ret = 0;
+    uint32_t offset;
+
+    for (i = 0; i < ARRAY_SIZE(x86_ext_save_areas); i++) {
+        const ExtSaveArea *esa = &x86_ext_save_areas[i];
+        offset = i > 1 ? ret : esa->offset;
+        if ((mask >> i) & 1) {
+            ret = MAX(ret, offset + esa->size);
+        }
+    }
+    return ret;
+}
+
 static inline uint64_t x86_cpu_xsave_components(X86CPU *cpu)
 {
     return ((uint64_t)cpu->env.features[FEAT_XSAVE_COMP_HI]) << 32 |
            cpu->env.features[FEAT_XSAVE_COMP_LO];
 }
 
+static inline uint64_t x86_cpu_xsave_sv_components(X86CPU *cpu)
+{
+    return ((uint64_t)cpu->env.features[FEAT_XSAVE_SV_HI]) << 32 |
+           cpu->env.features[FEAT_XSAVE_SV_LO];
+}
+
 const char *get_register_name_32(unsigned int reg)
 {
     if (reg >= CPU_NB_REGS32) {
@@ -4913,8 +4935,10 @@  static void x86_cpu_enable_xsave_components(X86CPU *cpu)
         }
     }
 
-    env->features[FEAT_XSAVE_COMP_LO] = mask;
+    env->features[FEAT_XSAVE_COMP_LO] = mask & CPUID_XSTATE_USER_MASK;
     env->features[FEAT_XSAVE_COMP_HI] = mask >> 32;
+    env->features[FEAT_XSAVE_SV_LO] = mask & CPUID_XSTATE_KERNEL_MASK;
+    env->features[FEAT_XSAVE_SV_HI] = mask >> 32;
 }
 
 /***** Steps involved on loading and filtering CPUID data