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#ifndef _ASM_X86_TLBFLUSH_H
#define _ASM_X86_TLBFLUSH_H
#include <linux/mm.h>
#include <linux/sched.h>
#include <asm/processor.h>
#include <asm/cpufeature.h>
#include <asm/special_insns.h>
#include <asm/smp.h>
static inline void __invpcid(unsigned long pcid, unsigned long addr,
unsigned long type)
{
struct { u64 d[2]; } desc = { { pcid, addr } };
/*
* The memory clobber is because the whole point is to invalidate
* stale TLB entries and, especially if we're flushing global
* mappings, we don't want the compiler to reorder any subsequent
* memory accesses before the TLB flush.
*
* The hex opcode is invpcid (%ecx), %eax in 32-bit mode and
* invpcid (%rcx), %rax in long mode.
*/
asm volatile (".byte 0x66, 0x0f, 0x38, 0x82, 0x01"
: : "m" (desc), "a" (type), "c" (&desc) : "memory");
}
#define INVPCID_TYPE_INDIV_ADDR 0
#define INVPCID_TYPE_SINGLE_CTXT 1
#define INVPCID_TYPE_ALL_INCL_GLOBAL 2
#define INVPCID_TYPE_ALL_NON_GLOBAL 3
/* Flush all mappings for a given pcid and addr, not including globals. */
static inline void invpcid_flush_one(unsigned long pcid,
unsigned long addr)
{
__invpcid(pcid, addr, INVPCID_TYPE_INDIV_ADDR);
}
/* Flush all mappings for a given PCID, not including globals. */
static inline void invpcid_flush_single_context(unsigned long pcid)
{
__invpcid(pcid, 0, INVPCID_TYPE_SINGLE_CTXT);
}
/* Flush all mappings, including globals, for all PCIDs. */
static inline void invpcid_flush_all(void)
{
__invpcid(0, 0, INVPCID_TYPE_ALL_INCL_GLOBAL);
}
/* Flush all mappings for all PCIDs except globals. */
static inline void invpcid_flush_all_nonglobals(void)
{
__invpcid(0, 0, INVPCID_TYPE_ALL_NON_GLOBAL);
}
#ifdef CONFIG_PARAVIRT
#include <asm/paravirt.h>
#else
#define __flush_tlb() __native_flush_tlb()
#define __flush_tlb_global() __native_flush_tlb_global()
#define __flush_tlb_single(addr) __native_flush_tlb_single(addr)
#endif
struct tlb_state {
struct mm_struct *active_mm;
int state;
/* Last user mm for optimizing IBPB */
union {
struct mm_struct *last_user_mm;
unsigned long last_user_mm_ibpb;
};
/*
* Access to this CR4 shadow and to H/W CR4 is protected by
* disabling interrupts when modifying either one.
*/
unsigned long cr4;
};
DECLARE_PER_CPU_SHARED_ALIGNED(struct tlb_state, cpu_tlbstate);
/* Initialize cr4 shadow for this CPU. */
static inline void cr4_init_shadow(void)
{
this_cpu_write(cpu_tlbstate.cr4, __read_cr4_safe());
}
/* Set in this cpu's CR4. */
static inline void cr4_set_bits(unsigned long mask)
{
unsigned long cr4;
cr4 = this_cpu_read(cpu_tlbstate.cr4);
if ((cr4 | mask) != cr4) {
cr4 |= mask;
this_cpu_write(cpu_tlbstate.cr4, cr4);
__write_cr4(cr4);
}
}
/* Clear in this cpu's CR4. */
static inline void cr4_clear_bits(unsigned long mask)
{
unsigned long cr4;
cr4 = this_cpu_read(cpu_tlbstate.cr4);
if ((cr4 & ~mask) != cr4) {
cr4 &= ~mask;
this_cpu_write(cpu_tlbstate.cr4, cr4);
__write_cr4(cr4);
}
}
static inline void cr4_toggle_bits(unsigned long mask)
{
unsigned long cr4;
cr4 = this_cpu_read(cpu_tlbstate.cr4);
cr4 ^= mask;
this_cpu_write(cpu_tlbstate.cr4, cr4);
__write_cr4(cr4);
}
/* Read the CR4 shadow. */
static inline unsigned long cr4_read_shadow(void)
{
return this_cpu_read(cpu_tlbstate.cr4);
}
/*
* Save some of cr4 feature set we're using (e.g. Pentium 4MB
* enable and PPro Global page enable), so that any CPU's that boot
* up after us can get the correct flags. This should only be used
* during boot on the boot cpu.
*/
extern unsigned long mmu_cr4_features;
extern u32 *trampoline_cr4_features;
static inline void cr4_set_bits_and_update_boot(unsigned long mask)
{
mmu_cr4_features |= mask;
if (trampoline_cr4_features)
*trampoline_cr4_features = mmu_cr4_features;
cr4_set_bits(mask);
}
/*
* Declare a couple of kaiser interfaces here for convenience,
* to avoid the need for asm/kaiser.h in unexpected places.
*/
#ifdef CONFIG_PAGE_TABLE_ISOLATION
extern int kaiser_enabled;
extern void kaiser_setup_pcid(void);
extern void kaiser_flush_tlb_on_return_to_user(void);
#else
#define kaiser_enabled 0
static inline void kaiser_setup_pcid(void)
{
}
static inline void kaiser_flush_tlb_on_return_to_user(void)
{
}
#endif
static inline void __native_flush_tlb(void)
{
/*
* If current->mm == NULL then we borrow a mm which may change during a
* task switch and therefore we must not be preempted while we write CR3
* back:
*/
preempt_disable();
if (kaiser_enabled)
kaiser_flush_tlb_on_return_to_user();
native_write_cr3(native_read_cr3());
preempt_enable();
}
static inline void __native_flush_tlb_global_irq_disabled(void)
{
unsigned long cr4;
cr4 = this_cpu_read(cpu_tlbstate.cr4);
if (cr4 & X86_CR4_PGE) {
/* clear PGE and flush TLB of all entries */
native_write_cr4(cr4 & ~X86_CR4_PGE);
/* restore PGE as it was before */
native_write_cr4(cr4);
} else {
/* do it with cr3, letting kaiser flush user PCID */
__native_flush_tlb();
}
}
static inline void __native_flush_tlb_global(void)
{
unsigned long flags;
if (this_cpu_has(X86_FEATURE_INVPCID)) {
/*
* Using INVPCID is considerably faster than a pair of writes
* to CR4 sandwiched inside an IRQ flag save/restore.
*/
invpcid_flush_all();
return;
}
/*
* Read-modify-write to CR4 - protect it from preemption and
* from interrupts. (Use the raw variant because this code can
* be called from deep inside debugging code.)
*/
raw_local_irq_save(flags);
__native_flush_tlb_global_irq_disabled();
raw_local_irq_restore(flags);
}
static inline void __native_flush_tlb_single(unsigned long addr)
{
/*
* SIMICS #GP's if you run INVPCID with type 2/3
* and X86_CR4_PCIDE clear. Shame!
*
* The ASIDs used below are hard-coded. But, we must not
* call invpcid(type=1/2) before CR4.PCIDE=1. Just call
* invlpg in the case we are called early.
*/
if (!this_cpu_has(X86_FEATURE_INVPCID_SINGLE)) {
if (kaiser_enabled)
kaiser_flush_tlb_on_return_to_user();
asm volatile("invlpg (%0)" ::"r" (addr) : "memory");
return;
}
/* Flush the address out of both PCIDs. */
/*
* An optimization here might be to determine addresses
* that are only kernel-mapped and only flush the kernel
* ASID. But, userspace flushes are probably much more
* important performance-wise.
*
* Make sure to do only a single invpcid when KAISER is
* disabled and we have only a single ASID.
*/
if (kaiser_enabled)
invpcid_flush_one(X86_CR3_PCID_ASID_USER, addr);
invpcid_flush_one(X86_CR3_PCID_ASID_KERN, addr);
}
static inline void __flush_tlb_all(void)
{
__flush_tlb_global();
/*
* Note: if we somehow had PCID but not PGE, then this wouldn't work --
* we'd end up flushing kernel translations for the current ASID but
* we might fail to flush kernel translations for other cached ASIDs.
*
* To avoid this issue, we force PCID off if PGE is off.
*/
}
static inline void __flush_tlb_one(unsigned long addr)
{
count_vm_tlb_event(NR_TLB_LOCAL_FLUSH_ONE);
__flush_tlb_single(addr);
}
#define TLB_FLUSH_ALL -1UL
/*
* TLB flushing:
*
* - flush_tlb_all() flushes all processes TLBs
* - flush_tlb_mm(mm) flushes the specified mm context TLB's
* - flush_tlb_page(vma, vmaddr) flushes one page
* - flush_tlb_range(vma, start, end) flushes a range of pages
* - flush_tlb_kernel_range(start, end) flushes a range of kernel pages
* - flush_tlb_others(cpumask, mm, start, end) flushes TLBs on other cpus
*
* ..but the i386 has somewhat limited tlb flushing capabilities,
* and page-granular flushes are available only on i486 and up.
*/
#define local_flush_tlb() __flush_tlb()
#define flush_tlb_mm(mm) flush_tlb_mm_range(mm, 0UL, TLB_FLUSH_ALL, 0UL)
#define flush_tlb_range(vma, start, end) \
flush_tlb_mm_range(vma->vm_mm, start, end, vma->vm_flags)
extern void flush_tlb_all(void);
extern void flush_tlb_mm_range(struct mm_struct *mm, unsigned long start,
unsigned long end, unsigned long vmflag);
extern void flush_tlb_kernel_range(unsigned long start, unsigned long end);
static inline void flush_tlb_page(struct vm_area_struct *vma, unsigned long a)
{
flush_tlb_mm_range(vma->vm_mm, a, a + PAGE_SIZE, VM_NONE);
}
void native_flush_tlb_others(const struct cpumask *cpumask,
struct mm_struct *mm,
unsigned long start, unsigned long end);
#define TLBSTATE_OK 1
#define TLBSTATE_LAZY 2
static inline void reset_lazy_tlbstate(void)
{
this_cpu_write(cpu_tlbstate.state, 0);
this_cpu_write(cpu_tlbstate.active_mm, &init_mm);
}
#ifndef CONFIG_PARAVIRT
#define flush_tlb_others(mask, mm, start, end) \
native_flush_tlb_others(mask, mm, start, end)
#endif
#endif /* _ASM_X86_TLBFLUSH_H */
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