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Diffstat (limited to 'arch/x86/kernel/cpu/mtrr/generic.c')
-rw-r--r--arch/x86/kernel/cpu/mtrr/generic.c74
1 files changed, 0 insertions, 74 deletions
diff --git a/arch/x86/kernel/cpu/mtrr/generic.c b/arch/x86/kernel/cpu/mtrr/generic.c
index 0db0770e75f6..396cb1eb1171 100644
--- a/arch/x86/kernel/cpu/mtrr/generic.c
+++ b/arch/x86/kernel/cpu/mtrr/generic.c
@@ -731,80 +731,6 @@ void mtrr_enable(void)
mtrr_wrmsr(MSR_MTRRdefType, deftype_lo, deftype_hi);
}
-/*
- * Disable and enable caches. Needed for changing MTRRs and the PAT MSR.
- *
- * Since we are disabling the cache don't allow any interrupts,
- * they would run extremely slow and would only increase the pain.
- *
- * The caller must ensure that local interrupts are disabled and
- * are reenabled after cache_enable() has been called.
- */
-static unsigned long saved_cr4;
-static DEFINE_RAW_SPINLOCK(cache_disable_lock);
-
-void cache_disable(void) __acquires(cache_disable_lock)
-{
- unsigned long cr0;
-
- /*
- * Note that this is not ideal
- * since the cache is only flushed/disabled for this CPU while the
- * MTRRs are changed, but changing this requires more invasive
- * changes to the way the kernel boots
- */
-
- raw_spin_lock(&cache_disable_lock);
-
- /* Enter the no-fill (CD=1, NW=0) cache mode and flush caches. */
- cr0 = read_cr0() | X86_CR0_CD;
- write_cr0(cr0);
-
- /*
- * Cache flushing is the most time-consuming step when programming
- * the MTRRs. Fortunately, as per the Intel Software Development
- * Manual, we can skip it if the processor supports cache self-
- * snooping.
- */
- if (!static_cpu_has(X86_FEATURE_SELFSNOOP))
- wbinvd();
-
- /* Save value of CR4 and clear Page Global Enable (bit 7) */
- if (boot_cpu_has(X86_FEATURE_PGE)) {
- saved_cr4 = __read_cr4();
- __write_cr4(saved_cr4 & ~X86_CR4_PGE);
- }
-
- /* Flush all TLBs via a mov %cr3, %reg; mov %reg, %cr3 */
- count_vm_tlb_event(NR_TLB_LOCAL_FLUSH_ALL);
- flush_tlb_local();
-
- if (cpu_feature_enabled(X86_FEATURE_MTRR))
- mtrr_disable();
-
- /* Again, only flush caches if we have to. */
- if (!static_cpu_has(X86_FEATURE_SELFSNOOP))
- wbinvd();
-}
-
-void cache_enable(void) __releases(cache_disable_lock)
-{
- /* Flush TLBs (no need to flush caches - they are disabled) */
- count_vm_tlb_event(NR_TLB_LOCAL_FLUSH_ALL);
- flush_tlb_local();
-
- if (cpu_feature_enabled(X86_FEATURE_MTRR))
- mtrr_enable();
-
- /* Enable caches */
- write_cr0(read_cr0() & ~X86_CR0_CD);
-
- /* Restore value of CR4 */
- if (boot_cpu_has(X86_FEATURE_PGE))
- __write_cr4(saved_cr4);
- raw_spin_unlock(&cache_disable_lock);
-}
-
static void generic_set_all(void)
{
unsigned long mask, count;