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Subject[PATCH 2/3] x86/mtrr: split common funcs from generic.c
Date
This is a preparation for make PAT(Page Attribute Table) independent
from MTRR(Memory Type Range Register).
It renames prefix of common functions in mtrr/generic.c from mtrr_ to
mtrr_pat_ which are commonly used by both MTRR and PAT and moves out
them from mtrr/generic.c to rendezvous.c.
Only prefix rename and movement, no logic change.

Signed-off-by: Isaku Yamahata <isaku.yamahata@gmail.com>
---
arch/x86/include/asm/mtrr.h | 4 +
arch/x86/kernel/cpu/mtrr/generic.c | 111 ++------------------------
arch/x86/kernel/cpu/mtrr/mtrr.c | 2 +-
arch/x86/kernel/cpu/mtrr/mtrr.h | 3 +-
arch/x86/kernel/cpu/mtrr/rendezvous.c | 91 +++++++++++++++++++++
5 files changed, 106 insertions(+), 105 deletions(-)

diff --git a/arch/x86/include/asm/mtrr.h b/arch/x86/include/asm/mtrr.h
index d90e87c55302..5b056374f5a6 100644
--- a/arch/x86/include/asm/mtrr.h
+++ b/arch/x86/include/asm/mtrr.h
@@ -33,6 +33,8 @@
*/
# ifdef CONFIG_MTRR
extern bool mtrr_enabled(void);
+extern void mtrr_pat_prepare_set(void) __acquires(set_atomicity_lock);
+extern void mtrr_pat_post_set(void) __releases(set_atomicity_lock);
extern u8 mtrr_type_lookup(u64 addr, u64 end, u8 *uniform);
extern void mtrr_save_fixed_ranges(void *);
extern void mtrr_save_state(void);
@@ -55,6 +57,8 @@ static inline bool mtrr_enabled(void)
{
return false;
}
+static inline void mtrr_pat_prepare_set(void) { };
+static inline void mtrr_pat_post_set(void) { };
static inline u8 mtrr_type_lookup(u64 addr, u64 end, u8 *uniform)
{
/*
diff --git a/arch/x86/kernel/cpu/mtrr/generic.c b/arch/x86/kernel/cpu/mtrr/generic.c
index aa5c064a6a22..a44f05f64846 100644
--- a/arch/x86/kernel/cpu/mtrr/generic.c
+++ b/arch/x86/kernel/cpu/mtrr/generic.c
@@ -397,9 +397,6 @@ print_fixed(unsigned base, unsigned step, const mtrr_type *types)
}
}

-static void prepare_set(void);
-static void post_set(void);
-
static void __init print_mtrr_state(void)
{
unsigned int i;
@@ -445,20 +442,6 @@ static void __init print_mtrr_state(void)
pr_debug("TOM2: %016llx aka %lldM\n", mtrr_tom2, mtrr_tom2>>20);
}

-/* PAT setup for BP. We need to go through sync steps here */
-void __init mtrr_bp_pat_init(void)
-{
- unsigned long flags;
-
- local_irq_save(flags);
- prepare_set();
-
- pat_init();
-
- post_set();
- local_irq_restore(flags);
-}
-
/* Grab all of the MTRR state for this CPU into *state */
bool __init get_mtrr_state(void)
{
@@ -680,8 +663,6 @@ static bool set_mtrr_var_ranges(unsigned int index, struct mtrr_var_range *vr)
return changed;
}

-static u32 deftype_lo, deftype_hi;
-
/**
* set_mtrr_state - Set the MTRR state for this CPU.
*
@@ -705,100 +686,24 @@ static unsigned long set_mtrr_state(void)
* Set_mtrr_restore restores the old value of MTRRdefType,
* so to set it we fiddle with the saved value:
*/
- if ((deftype_lo & 0xff) != mtrr_state.def_type
- || ((deftype_lo & 0xc00) >> 10) != mtrr_state.enabled) {
+ if ((mtrr_deftype_lo & 0xff) != mtrr_state.def_type
+ || ((mtrr_deftype_lo & 0xc00) >> 10) != mtrr_state.enabled) {

- deftype_lo = (deftype_lo & ~0xcff) | mtrr_state.def_type |
- (mtrr_state.enabled << 10);
+ mtrr_deftype_lo = (mtrr_deftype_lo & ~0xcff) |
+ mtrr_state.def_type | (mtrr_state.enabled << 10);
change_mask |= MTRR_CHANGE_MASK_DEFTYPE;
}

return change_mask;
}

-
-static unsigned long cr4;
-static DEFINE_RAW_SPINLOCK(set_atomicity_lock);
-
-/*
- * 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 post_set() has been called.
- */
-static void prepare_set(void) __acquires(set_atomicity_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(&set_atomicity_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)) {
- cr4 = __read_cr4();
- __write_cr4(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();
-
- /* Save MTRR state */
- rdmsr(MSR_MTRRdefType, deftype_lo, deftype_hi);
-
- /* Disable MTRRs, and set the default type to uncached */
- mtrr_wrmsr(MSR_MTRRdefType, deftype_lo & ~0xcff, deftype_hi);
-
- /* Again, only flush caches if we have to. */
- if (!static_cpu_has(X86_FEATURE_SELFSNOOP))
- wbinvd();
-}
-
-static void post_set(void) __releases(set_atomicity_lock)
-{
- /* Flush TLBs (no need to flush caches - they are disabled) */
- count_vm_tlb_event(NR_TLB_LOCAL_FLUSH_ALL);
- __flush_tlb();
-
- /* Intel (P6) standard MTRRs */
- mtrr_wrmsr(MSR_MTRRdefType, deftype_lo, deftype_hi);
-
- /* Enable caches */
- write_cr0(read_cr0() & ~X86_CR0_CD);
-
- /* Restore value of CR4 */
- if (boot_cpu_has(X86_FEATURE_PGE))
- __write_cr4(cr4);
- raw_spin_unlock(&set_atomicity_lock);
-}
-
static void generic_set_all(void)
{
unsigned long mask, count;
unsigned long flags;

local_irq_save(flags);
- prepare_set();
+ mtrr_pat_prepare_set();

/* Actually set the state */
mask = set_mtrr_state();
@@ -806,7 +711,7 @@ static void generic_set_all(void)
/* also set PAT */
pat_init();

- post_set();
+ mtrr_pat_post_set();
local_irq_restore(flags);

/* Use the atomic bitops to update the global mask */
@@ -837,7 +742,7 @@ static void generic_set_mtrr(unsigned int reg, unsigned long base,
vr = &mtrr_state.var_ranges[reg];

local_irq_save(flags);
- prepare_set();
+ mtrr_pat_prepare_set();

if (size == 0) {
/*
@@ -856,7 +761,7 @@ static void generic_set_mtrr(unsigned int reg, unsigned long base,
mtrr_wrmsr(MTRRphysMask_MSR(reg), vr->mask_lo, vr->mask_hi);
}

- post_set();
+ mtrr_pat_post_set();
local_irq_restore(flags);
}

diff --git a/arch/x86/kernel/cpu/mtrr/mtrr.c b/arch/x86/kernel/cpu/mtrr/mtrr.c
index 3d35edb1aa42..475627ca2c1b 100644
--- a/arch/x86/kernel/cpu/mtrr/mtrr.c
+++ b/arch/x86/kernel/cpu/mtrr/mtrr.c
@@ -646,7 +646,7 @@ void __init mtrr_pat_bp_init(void)
__mtrr_enabled = get_mtrr_state();

if (mtrr_enabled())
- mtrr_bp_pat_init();
+ pat_bp_init();

if (mtrr_cleanup(phys_addr)) {
changed_by_mtrr_cleanup = 1;
diff --git a/arch/x86/kernel/cpu/mtrr/mtrr.h b/arch/x86/kernel/cpu/mtrr/mtrr.h
index e9aeeeac9a3e..57948b651b8e 100644
--- a/arch/x86/kernel/cpu/mtrr/mtrr.h
+++ b/arch/x86/kernel/cpu/mtrr/mtrr.h
@@ -53,7 +53,7 @@ void set_mtrr_prepare_save(struct set_mtrr_context *ctxt);
void fill_mtrr_var_range(unsigned int index,
u32 base_lo, u32 base_hi, u32 mask_lo, u32 mask_hi);
bool get_mtrr_state(void);
-void mtrr_bp_pat_init(void);
+void pat_bp_init(void);

extern void __init set_mtrr_ops(const struct mtrr_ops *ops);

@@ -76,6 +76,7 @@ void set_mtrr_pat(unsigned int reg, unsigned long base,
unsigned long size, mtrr_type type);
void set_mtrr_pat_cpuslocked(unsigned int reg, unsigned long base,
unsigned long size, mtrr_type type);
+extern u32 mtrr_deftype_lo, mtrr_deftype_hi;

/* CPU specific mtrr init functions */
int amd_init_mtrr(void);
diff --git a/arch/x86/kernel/cpu/mtrr/rendezvous.c b/arch/x86/kernel/cpu/mtrr/rendezvous.c
index 5448eea573df..d902b9e5cc17 100644
--- a/arch/x86/kernel/cpu/mtrr/rendezvous.c
+++ b/arch/x86/kernel/cpu/mtrr/rendezvous.c
@@ -33,14 +33,105 @@
#define DEBUG

#include <linux/stop_machine.h>
+#include <linux/vmstat.h>

#include <asm/mtrr.h>
#include <asm/msr.h>
#include <asm/pat.h>
+#include <asm/tlbflush.h>

#include "mtrr.h"

static bool mtrr_pat_aps_delayed_init;
+u32 mtrr_deftype_lo, mtrr_deftype_hi;
+static unsigned long cr4;
+static DEFINE_RAW_SPINLOCK(set_atomicity_lock);
+
+/* PAT setup for BP. We need to go through sync steps here */
+void __init pat_bp_init(void)
+{
+ unsigned long flags;
+
+ local_irq_save(flags);
+ mtrr_pat_prepare_set();
+
+ pat_init();
+
+ mtrr_pat_post_set();
+ local_irq_restore(flags);
+}
+
+/*
+ * 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 mtrr_pat_post_set() has been called.
+ */
+void mtrr_pat_prepare_set(void) __acquires(set_atomicity_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(&set_atomicity_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)) {
+ cr4 = __read_cr4();
+ __write_cr4(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();
+
+ /* Save MTRR state */
+ rdmsr(MSR_MTRRdefType, mtrr_deftype_lo, mtrr_deftype_hi);
+
+ /* Disable MTRRs, and set the default type to uncached */
+ mtrr_wrmsr(MSR_MTRRdefType, mtrr_deftype_lo & ~0xcff, mtrr_deftype_hi);
+
+ /* Again, only flush caches if we have to. */
+ if (!static_cpu_has(X86_FEATURE_SELFSNOOP))
+ wbinvd();
+}
+
+void mtrr_pat_post_set(void) __releases(set_atomicity_lock)
+{
+ /* Flush TLBs (no need to flush caches - they are disabled) */
+ count_vm_tlb_event(NR_TLB_LOCAL_FLUSH_ALL);
+ __flush_tlb();
+
+ /* Intel (P6) standard MTRRs */
+ mtrr_wrmsr(MSR_MTRRdefType, mtrr_deftype_lo, mtrr_deftype_hi);
+
+ /* Enable caches */
+ write_cr0(read_cr0() & ~X86_CR0_CD);
+
+ /* Restore value of CR4 */
+ if (boot_cpu_has(X86_FEATURE_PGE))
+ __write_cr4(cr4);
+ raw_spin_unlock(&set_atomicity_lock);
+}

struct set_mtrr_data {
unsigned long smp_base;
--
2.17.1
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