x86/fpu: Rename copy_xregs_to_kernel() and copy_kernel_to_xregs()

[linux-2.6-microblaze.git] / arch / x86 / include / asm / fpu / internal.h

diff --git a/arch/x86/include/asm/fpu/internal.h b/arch/x86/include/asm/fpu/internal.h
index ceeba9f..dae1545 100644 (file)
--- a/arch/x86/include/asm/fpu/internal.h
+++ b/arch/x86/include/asm/fpu/internal.h
@@ -26,8 +26,6 @@
 /*
  * High level FPU state handling functions:
  */
-extern void fpu__prepare_read(struct fpu *fpu);
-extern void fpu__prepare_write(struct fpu *fpu);
 extern void fpu__save(struct fpu *fpu);
 extern int  fpu__restore_sig(void __user *buf, int ia32_frame);
 extern void fpu__drop(struct fpu *fpu);
@@ -45,7 +43,6 @@ extern void fpu__init_cpu_xstate(void);
 extern void fpu__init_system(struct cpuinfo_x86 *c);
 extern void fpu__init_check_bugs(void);
 extern void fpu__resume_cpu(void);
-extern u64 fpu__get_supported_xfeatures_mask(void);
 
 /*
  * Debugging facility:
@@ -87,22 +84,6 @@ extern void fpstate_init_soft(struct swregs_state *soft);
 static inline void fpstate_init_soft(struct swregs_state *soft) {}
 #endif
 
-static inline void fpstate_init_xstate(struct xregs_state *xsave)
-{
-       /*
-        * XRSTORS requires these bits set in xcomp_bv, or it will
-        * trigger #GP:
-        */
-       xsave->header.xcomp_bv = XCOMP_BV_COMPACTED_FORMAT | xfeatures_mask_all;
-}
-
-static inline void fpstate_init_fxstate(struct fxregs_state *fx)
-{
-       fx->cwd = 0x37f;
-       fx->mxcsr = MXCSR_DEFAULT;
-}
-extern void fpstate_sanitize_xstate(struct fpu *fpu);
-
 #define user_insn(insn, output, input...)                              \
 ({                                                                     \
        int err;                                                        \
@@ -204,6 +185,14 @@ static inline void copy_fxregs_to_kernel(struct fpu *fpu)
                asm volatile("fxsaveq %[fx]" : [fx] "=m" (fpu->state.fxsave));
 }
 
+static inline void fxsave(struct fxregs_state *fx)
+{
+       if (IS_ENABLED(CONFIG_X86_32))
+               asm volatile( "fxsave %[fx]" : [fx] "=m" (*fx));
+       else
+               asm volatile("fxsaveq %[fx]" : [fx] "=m" (*fx));
+}
+
 /* These macros all use (%edi)/(%rdi) as the single memory argument. */
 #define XSAVE          ".byte " REX_PREFIX "0x0f,0xae,0x27"
 #define XSAVEOPT       ".byte " REX_PREFIX "0x0f,0xae,0x37"
@@ -272,29 +261,7 @@ static inline void copy_fxregs_to_kernel(struct fpu *fpu)
  * This function is called only during boot time when x86 caps are not set
  * up and alternative can not be used yet.
  */
-static inline void copy_xregs_to_kernel_booting(struct xregs_state *xstate)
-{
-       u64 mask = xfeatures_mask_all;
-       u32 lmask = mask;
-       u32 hmask = mask >> 32;
-       int err;
-
-       WARN_ON(system_state != SYSTEM_BOOTING);
-
-       if (boot_cpu_has(X86_FEATURE_XSAVES))
-               XSTATE_OP(XSAVES, xstate, lmask, hmask, err);
-       else
-               XSTATE_OP(XSAVE, xstate, lmask, hmask, err);
-
-       /* We should never fault when copying to a kernel buffer: */
-       WARN_ON_FPU(err);
-}
-
-/*
- * This function is called only during boot time when x86 caps are not set
- * up and alternative can not be used yet.
- */
-static inline void copy_kernel_to_xregs_booting(struct xregs_state *xstate)
+static inline void os_xrstor_booting(struct xregs_state *xstate)
 {
        u64 mask = -1;
        u32 lmask = mask;
@@ -317,8 +284,11 @@ static inline void copy_kernel_to_xregs_booting(struct xregs_state *xstate)
 
 /*
  * Save processor xstate to xsave area.
+ *
+ * Uses either XSAVE or XSAVEOPT or XSAVES depending on the CPU features
+ * and command line options. The choice is permanent until the next reboot.
  */
-static inline void copy_xregs_to_kernel(struct xregs_state *xstate)
+static inline void os_xsave(struct xregs_state *xstate)
 {
        u64 mask = xfeatures_mask_all;
        u32 lmask = mask;
@@ -335,8 +305,10 @@ static inline void copy_xregs_to_kernel(struct xregs_state *xstate)
 
 /*
  * Restore processor xstate from xsave area.
+ *
+ * Uses XRSTORS when XSAVES is used, XRSTOR otherwise.
  */
-static inline void copy_kernel_to_xregs(struct xregs_state *xstate, u64 mask)
+static inline void os_xrstor(struct xregs_state *xstate, u64 mask)
 {
        u32 lmask = mask;
        u32 hmask = mask >> 32;
@@ -397,13 +369,13 @@ static inline int copy_user_to_xregs(struct xregs_state __user *buf, u64 mask)
  * Restore xstate from kernel space xsave area, return an error code instead of
  * an exception.
  */
-static inline int copy_kernel_to_xregs_err(struct xregs_state *xstate, u64 mask)
+static inline int os_xrstor_safe(struct xregs_state *xstate, u64 mask)
 {
        u32 lmask = mask;
        u32 hmask = mask >> 32;
        int err;
 
-       if (static_cpu_has(X86_FEATURE_XSAVES))
+       if (cpu_feature_enabled(X86_FEATURE_XSAVES))
                XSTATE_OP(XRSTORS, xstate, lmask, hmask, err);
        else
                XSTATE_OP(XRSTOR, xstate, lmask, hmask, err);
@@ -416,7 +388,7 @@ extern int copy_fpregs_to_fpstate(struct fpu *fpu);
 static inline void __copy_kernel_to_fpregs(union fpregs_state *fpstate, u64 mask)
 {
        if (use_xsave()) {
-               copy_kernel_to_xregs(&fpstate->xsave, mask);
+               os_xrstor(&fpstate->xsave, mask);
        } else {
                if (use_fxsr())
                        copy_kernel_to_fxregs(&fpstate->fxsave);
@@ -578,10 +550,17 @@ static inline void switch_fpu_finish(struct fpu *new_fpu)
         * PKRU state is switched eagerly because it needs to be valid before we
         * return to userland e.g. for a copy_to_user() operation.
         */
-       if (current->mm) {
+       if (!(current->flags & PF_KTHREAD)) {
+               /*
+                * If the PKRU bit in xsave.header.xfeatures is not set,
+                * then the PKRU component was in init state, which means
+                * XRSTOR will set PKRU to 0. If the bit is not set then
+                * get_xsave_addr() will return NULL because the PKRU value
+                * in memory is not valid. This means pkru_val has to be
+                * set to 0 and not to init_pkru_value.
+                */
                pk = get_xsave_addr(&new_fpu->state.xsave, XFEATURE_PKRU);
-               if (pk)
-                       pkru_val = pk->pkru;
+               pkru_val = pk ? pk->pkru : 0;
        }
        __write_pkru(pkru_val);
 }