[PATCH 079/208] x86/fpu: Rename 'pcntxt_mask' to 'xfeatures_mask'

From: Ingo Molnar
Date: Tue May 05 2015 - 12:46:54 EST


So the 'pcntxt_mask' is a misnomer, it's essentially meaningless to anyone
who doesn't know what it does exactly.

Name it more descriptively as 'xfeatures_mask'.

Reviewed-by: Borislav Petkov <bp@xxxxxxxxx>
Cc: Andy Lutomirski <luto@xxxxxxxxxxxxxx>
Cc: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>
Cc: Fenghua Yu <fenghua.yu@xxxxxxxxx>
Cc: H. Peter Anvin <hpa@xxxxxxxxx>
Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Cc: Oleg Nesterov <oleg@xxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
---
arch/x86/include/asm/fpu/xsave.h | 2 +-
arch/x86/kernel/fpu/core.c | 2 +-
arch/x86/kernel/fpu/xsave.c | 58 +++++++++++++++++++++++++++++-----------------------------
arch/x86/power/cpu.c | 4 ++--
4 files changed, 33 insertions(+), 33 deletions(-)

diff --git a/arch/x86/include/asm/fpu/xsave.h b/arch/x86/include/asm/fpu/xsave.h
index 7c90ea93c54e..400d5b2e42eb 100644
--- a/arch/x86/include/asm/fpu/xsave.h
+++ b/arch/x86/include/asm/fpu/xsave.h
@@ -45,7 +45,7 @@
#endif

extern unsigned int xstate_size;
-extern u64 pcntxt_mask;
+extern u64 xfeatures_mask;
extern u64 xstate_fx_sw_bytes[USER_XSTATE_FX_SW_WORDS];
extern struct xsave_struct *init_xstate_buf;

diff --git a/arch/x86/kernel/fpu/core.c b/arch/x86/kernel/fpu/core.c
index 3094b37b101e..7b98da7e1b55 100644
--- a/arch/x86/kernel/fpu/core.c
+++ b/arch/x86/kernel/fpu/core.c
@@ -528,7 +528,7 @@ int xstateregs_set(struct task_struct *target, const struct user_regset *regset,
* mxcsr reserved bits must be masked to zero for security reasons.
*/
xsave->i387.mxcsr &= mxcsr_feature_mask;
- xsave->xsave_hdr.xstate_bv &= pcntxt_mask;
+ xsave->xsave_hdr.xstate_bv &= xfeatures_mask;
/*
* These bits must be zero.
*/
diff --git a/arch/x86/kernel/fpu/xsave.c b/arch/x86/kernel/fpu/xsave.c
index f39882b7281b..c0e95538d689 100644
--- a/arch/x86/kernel/fpu/xsave.c
+++ b/arch/x86/kernel/fpu/xsave.c
@@ -13,9 +13,9 @@
#include <asm/xcr.h>

/*
- * Supported feature mask by the CPU and the kernel.
+ * Mask of xstate features supported by the CPU and the kernel:
*/
-u64 pcntxt_mask;
+u64 xfeatures_mask;

/*
* Represents init state for the supported extended state.
@@ -24,7 +24,7 @@ struct xsave_struct *init_xstate_buf;

static struct _fpx_sw_bytes fx_sw_reserved, fx_sw_reserved_ia32;
static unsigned int *xstate_offsets, *xstate_sizes;
-static unsigned int xstate_comp_offsets[sizeof(pcntxt_mask)*8];
+static unsigned int xstate_comp_offsets[sizeof(xfeatures_mask)*8];
static unsigned int xstate_features;

/*
@@ -52,7 +52,7 @@ void __sanitize_i387_state(struct task_struct *tsk)
* None of the feature bits are in init state. So nothing else
* to do for us, as the memory layout is up to date.
*/
- if ((xstate_bv & pcntxt_mask) == pcntxt_mask)
+ if ((xstate_bv & xfeatures_mask) == xfeatures_mask)
return;

/*
@@ -74,7 +74,7 @@ void __sanitize_i387_state(struct task_struct *tsk)
if (!(xstate_bv & XSTATE_SSE))
memset(&fx->xmm_space[0], 0, 256);

- xstate_bv = (pcntxt_mask & ~xstate_bv) >> 2;
+ xstate_bv = (xfeatures_mask & ~xstate_bv) >> 2;

/*
* Update all the other memory layouts for which the corresponding
@@ -291,7 +291,7 @@ sanitize_restored_xstate(struct task_struct *tsk,
if (fx_only)
xsave_hdr->xstate_bv = XSTATE_FPSSE;
else
- xsave_hdr->xstate_bv &= (pcntxt_mask & xstate_bv);
+ xsave_hdr->xstate_bv &= (xfeatures_mask & xstate_bv);
}

if (use_fxsr()) {
@@ -312,11 +312,11 @@ static inline int restore_user_xstate(void __user *buf, u64 xbv, int fx_only)
{
if (use_xsave()) {
if ((unsigned long)buf % 64 || fx_only) {
- u64 init_bv = pcntxt_mask & ~XSTATE_FPSSE;
+ u64 init_bv = xfeatures_mask & ~XSTATE_FPSSE;
xrstor_state(init_xstate_buf, init_bv);
return fxrstor_user(buf);
} else {
- u64 init_bv = pcntxt_mask & ~xbv;
+ u64 init_bv = xfeatures_mask & ~xbv;
if (unlikely(init_bv))
xrstor_state(init_xstate_buf, init_bv);
return xrestore_user(buf, xbv);
@@ -439,7 +439,7 @@ static void prepare_fx_sw_frame(void)

fx_sw_reserved.magic1 = FP_XSTATE_MAGIC1;
fx_sw_reserved.extended_size = size;
- fx_sw_reserved.xstate_bv = pcntxt_mask;
+ fx_sw_reserved.xstate_bv = xfeatures_mask;
fx_sw_reserved.xstate_size = xstate_size;

if (config_enabled(CONFIG_IA32_EMULATION)) {
@@ -454,7 +454,7 @@ static void prepare_fx_sw_frame(void)
static inline void xstate_enable(void)
{
cr4_set_bits(X86_CR4_OSXSAVE);
- xsetbv(XCR_XFEATURE_ENABLED_MASK, pcntxt_mask);
+ xsetbv(XCR_XFEATURE_ENABLED_MASK, xfeatures_mask);
}

/*
@@ -465,7 +465,7 @@ static void __init setup_xstate_features(void)
{
int eax, ebx, ecx, edx, leaf = 0x2;

- xstate_features = fls64(pcntxt_mask);
+ xstate_features = fls64(xfeatures_mask);
xstate_offsets = alloc_bootmem(xstate_features * sizeof(int));
xstate_sizes = alloc_bootmem(xstate_features * sizeof(int));

@@ -484,7 +484,7 @@ static void __init setup_xstate_features(void)

static void print_xstate_feature(u64 xstate_mask, const char *desc)
{
- if (pcntxt_mask & xstate_mask) {
+ if (xfeatures_mask & xstate_mask) {
int xstate_feature = fls64(xstate_mask)-1;

pr_info("x86/fpu: Supporting XSAVE feature %2d: '%s'\n", xstate_feature, desc);
@@ -516,7 +516,7 @@ static void print_xstate_features(void)
*/
void setup_xstate_comp(void)
{
- unsigned int xstate_comp_sizes[sizeof(pcntxt_mask)*8];
+ unsigned int xstate_comp_sizes[sizeof(xfeatures_mask)*8];
int i;

/*
@@ -529,7 +529,7 @@ void setup_xstate_comp(void)

if (!cpu_has_xsaves) {
for (i = 2; i < xstate_features; i++) {
- if (test_bit(i, (unsigned long *)&pcntxt_mask)) {
+ if (test_bit(i, (unsigned long *)&xfeatures_mask)) {
xstate_comp_offsets[i] = xstate_offsets[i];
xstate_comp_sizes[i] = xstate_sizes[i];
}
@@ -540,7 +540,7 @@ void setup_xstate_comp(void)
xstate_comp_offsets[2] = FXSAVE_SIZE + XSAVE_HDR_SIZE;

for (i = 2; i < xstate_features; i++) {
- if (test_bit(i, (unsigned long *)&pcntxt_mask))
+ if (test_bit(i, (unsigned long *)&xfeatures_mask))
xstate_comp_sizes[i] = xstate_sizes[i];
else
xstate_comp_sizes[i] = 0;
@@ -573,8 +573,8 @@ static void __init setup_init_fpu_buf(void)

if (cpu_has_xsaves) {
init_xstate_buf->xsave_hdr.xcomp_bv =
- (u64)1 << 63 | pcntxt_mask;
- init_xstate_buf->xsave_hdr.xstate_bv = pcntxt_mask;
+ (u64)1 << 63 | xfeatures_mask;
+ init_xstate_buf->xsave_hdr.xstate_bv = xfeatures_mask;
}

/*
@@ -604,7 +604,7 @@ __setup("eagerfpu=", eager_fpu_setup);


/*
- * Calculate total size of enabled xstates in XCR0/pcntxt_mask.
+ * Calculate total size of enabled xstates in XCR0/xfeatures_mask.
*/
static void __init init_xstate_size(void)
{
@@ -619,7 +619,7 @@ static void __init init_xstate_size(void)

xstate_size = FXSAVE_SIZE + XSAVE_HDR_SIZE;
for (i = 2; i < 64; i++) {
- if (test_bit(i, (unsigned long *)&pcntxt_mask)) {
+ if (test_bit(i, (unsigned long *)&xfeatures_mask)) {
cpuid_count(XSTATE_CPUID, i, &eax, &ebx, &ecx, &edx);
xstate_size += eax;
}
@@ -642,17 +642,17 @@ static void /* __init */ xstate_enable_boot_cpu(void)
}

cpuid_count(XSTATE_CPUID, 0, &eax, &ebx, &ecx, &edx);
- pcntxt_mask = eax + ((u64)edx << 32);
+ xfeatures_mask = eax + ((u64)edx << 32);

- if ((pcntxt_mask & XSTATE_FPSSE) != XSTATE_FPSSE) {
- pr_err("x86/fpu: FP/SSE not present amongst the CPU's xstate features: 0x%llx.\n", pcntxt_mask);
+ if ((xfeatures_mask & XSTATE_FPSSE) != XSTATE_FPSSE) {
+ pr_err("x86/fpu: FP/SSE not present amongst the CPU's xstate features: 0x%llx.\n", xfeatures_mask);
BUG();
}

/*
* Support only the state known to OS.
*/
- pcntxt_mask = pcntxt_mask & XCNTXT_MASK;
+ xfeatures_mask = xfeatures_mask & XCNTXT_MASK;

xstate_enable();

@@ -661,7 +661,7 @@ static void /* __init */ xstate_enable_boot_cpu(void)
*/
init_xstate_size();

- update_regset_xstate_info(xstate_size, pcntxt_mask);
+ update_regset_xstate_info(xstate_size, xfeatures_mask);
prepare_fx_sw_frame();
setup_init_fpu_buf();

@@ -669,18 +669,18 @@ static void /* __init */ xstate_enable_boot_cpu(void)
if (cpu_has_xsaveopt && eagerfpu != DISABLE)
eagerfpu = ENABLE;

- if (pcntxt_mask & XSTATE_EAGER) {
+ if (xfeatures_mask & XSTATE_EAGER) {
if (eagerfpu == DISABLE) {
pr_err("x86/fpu: eagerfpu switching disabled, disabling the following xstate features: 0x%llx.\n",
- pcntxt_mask & XSTATE_EAGER);
- pcntxt_mask &= ~XSTATE_EAGER;
+ xfeatures_mask & XSTATE_EAGER);
+ xfeatures_mask &= ~XSTATE_EAGER;
} else {
eagerfpu = ENABLE;
}
}

pr_info("x86/fpu: Enabled xstate features 0x%llx, context size is 0x%x bytes, using '%s' format.\n",
- pcntxt_mask,
+ xfeatures_mask,
xstate_size,
cpu_has_xsaves ? "compacted" : "standard");
}
@@ -749,7 +749,7 @@ void __init_refok eager_fpu_init(void)
void *get_xsave_addr(struct xsave_struct *xsave, int xstate)
{
int feature = fls64(xstate) - 1;
- if (!test_bit(feature, (unsigned long *)&pcntxt_mask))
+ if (!test_bit(feature, (unsigned long *)&xfeatures_mask))
return NULL;

return (void *)xsave + xstate_comp_offsets[feature];
diff --git a/arch/x86/power/cpu.c b/arch/x86/power/cpu.c
index edaf934c749e..62054acbd0d8 100644
--- a/arch/x86/power/cpu.c
+++ b/arch/x86/power/cpu.c
@@ -21,7 +21,7 @@
#include <asm/xcr.h>
#include <asm/suspend.h>
#include <asm/debugreg.h>
-#include <asm/fpu/internal.h> /* pcntxt_mask */
+#include <asm/fpu/internal.h> /* xfeatures_mask */
#include <asm/cpu.h>

#ifdef CONFIG_X86_32
@@ -225,7 +225,7 @@ static void notrace __restore_processor_state(struct saved_context *ctxt)
* restore XCR0 for xsave capable cpu's.
*/
if (cpu_has_xsave)
- xsetbv(XCR_XFEATURE_ENABLED_MASK, pcntxt_mask);
+ xsetbv(XCR_XFEATURE_ENABLED_MASK, xfeatures_mask);

fix_processor_context();

--
2.1.0

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