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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/system.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
/*
* Declare a couple of kaiser interfaces here for convenience,
* to avoid the need for asm/kaiser.h in unexpected places.
*/
#ifdef CONFIG_KAISER
extern void kaiser_setup_pcid(void);
extern void kaiser_flush_tlb_on_return_to_user(void);
#else
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 (this_cpu_has(X86_FEATURE_INVPCID)) {
/*
* Note, this works with CR4.PCIDE=0 or 1.
*/
invpcid_flush_all_nonglobals();
return;
}
/*
* 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 (this_cpu_has(X86_FEATURE_PCID))
kaiser_flush_tlb_on_return_to_user();
native_write_cr3(native_read_cr3());
preempt_enable();
}
static inline void __native_flush_tlb_global(void)
{
#ifdef CONFIG_KAISER
/* Globals are not used at all */
__native_flush_tlb();
#else
unsigned long flags;
unsigned long cr4;
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.
*
* Note, this works with CR4.PCIDE=0 or 1.
*/
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);
cr4 = native_read_cr4();
/* clear PGE */
native_write_cr4(cr4 & ~X86_CR4_PGE);
/* write old PGE again and flush TLBs */
native_write_cr4(cr4);
raw_local_irq_restore(flags);
#endif
}
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 (this_cpu_has(X86_FEATURE_PCID))
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 (X86_CR3_PCID_ASID_KERN != X86_CR3_PCID_ASID_USER)
invpcid_flush_one(X86_CR3_PCID_ASID_KERN, addr);
invpcid_flush_one(X86_CR3_PCID_ASID_USER, addr);
}
static inline void __flush_tlb_all(void)
{
if (cpu_has_pge)
__flush_tlb_global();
else
__flush_tlb();
/*
* 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)
{
if (cpu_has_invlpg)
__flush_tlb_single(addr);
else
__flush_tlb();
}
#ifdef CONFIG_X86_32
# define TLB_FLUSH_ALL 0xffffffff
#else
# define TLB_FLUSH_ALL -1ULL
#endif
/*
* TLB flushing:
*
* - flush_tlb() flushes the current mm struct TLBs
* - 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, va) 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()
extern void flush_tlb_all(void);
extern void flush_tlb_current_task(void);
extern void flush_tlb_mm(struct mm_struct *);
extern void flush_tlb_page(struct vm_area_struct *, unsigned long);
#define flush_tlb() flush_tlb_current_task()
static inline void flush_tlb_range(struct vm_area_struct *vma,
unsigned long start, unsigned long end)
{
flush_tlb_mm(vma->vm_mm);
}
void native_flush_tlb_others(const struct cpumask *cpumask,
struct mm_struct *mm, unsigned long va);
#define TLBSTATE_OK 1
#define TLBSTATE_LAZY 2
struct tlb_state {
struct mm_struct *active_mm;
int state;
};
DECLARE_PER_CPU_SHARED_ALIGNED(struct tlb_state, cpu_tlbstate);
static inline void reset_lazy_tlbstate(void)
{
percpu_write(cpu_tlbstate.state, 0);
percpu_write(cpu_tlbstate.active_mm, &init_mm);
}
#ifndef CONFIG_PARAVIRT
#define flush_tlb_others(mask, mm, va) native_flush_tlb_others(mask, mm, va)
#endif
static inline void flush_tlb_kernel_range(unsigned long start,
unsigned long end)
{
flush_tlb_all();
}
#endif /* _ASM_X86_TLBFLUSH_H */
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