linux/arch/arm64/include/asm/tlbflush.h
Catalin Marinas 858fbd7248 Merge branch 'for-next/c1-pro-erratum-4193714' into for-next/core
* for-next/c1-pro-erratum-4193714:
  : Work around C1-Pro erratum 4193714 (CVE-2026-0995)
  arm64: errata: Work around early CME DVMSync acknowledgement
  arm64: cputype: Add C1-Pro definitions
  arm64: tlb: Pass the corresponding mm to __tlbi_sync_s1ish()
  arm64: tlb: Introduce __tlbi_sync_s1ish_{kernel,batch}() for TLB maintenance
2026-04-20 13:12:35 +01:00

759 lines
21 KiB
C

/* SPDX-License-Identifier: GPL-2.0-only */
/*
* Based on arch/arm/include/asm/tlbflush.h
*
* Copyright (C) 1999-2003 Russell King
* Copyright (C) 2012 ARM Ltd.
*/
#ifndef __ASM_TLBFLUSH_H
#define __ASM_TLBFLUSH_H
#ifndef __ASSEMBLER__
#include <linux/bitfield.h>
#include <linux/mm_types.h>
#include <linux/sched.h>
#include <linux/mmu_notifier.h>
#include <asm/cputype.h>
#include <asm/mmu.h>
/*
* Raw TLBI operations.
*
* Where necessary, use the __tlbi() macro to avoid asm()
* boilerplate. Drivers and most kernel code should use the TLB
* management routines in preference to the macro below.
*
* The macro can be used as __tlbi(op) or __tlbi(op, arg), depending
* on whether a particular TLBI operation takes an argument or
* not. The macros handles invoking the asm with or without the
* register argument as appropriate.
*/
#define __TLBI_0(op, arg) asm (ARM64_ASM_PREAMBLE \
"tlbi " #op "\n" \
: : )
#define __TLBI_1(op, arg) asm (ARM64_ASM_PREAMBLE \
"tlbi " #op ", %x0\n" \
: : "rZ" (arg))
#define __TLBI_N(op, arg, n, ...) __TLBI_##n(op, arg)
#define __tlbi(op, ...) __TLBI_N(op, ##__VA_ARGS__, 1, 0)
#define __tlbi_user(op, arg) do { \
if (arm64_kernel_unmapped_at_el0()) \
__tlbi(op, (arg) | USER_ASID_FLAG); \
} while (0)
/* This macro creates a properly formatted VA operand for the TLBI */
#define __TLBI_VADDR(addr, asid) \
({ \
unsigned long __ta = (addr) >> 12; \
__ta &= GENMASK_ULL(43, 0); \
__ta |= (unsigned long)(asid) << 48; \
__ta; \
})
/*
* Get translation granule of the system, which is decided by
* PAGE_SIZE. Used by TTL.
* - 4KB : 1
* - 16KB : 2
* - 64KB : 3
*/
#define TLBI_TTL_TG_4K 1
#define TLBI_TTL_TG_16K 2
#define TLBI_TTL_TG_64K 3
static inline unsigned long get_trans_granule(void)
{
switch (PAGE_SIZE) {
case SZ_4K:
return TLBI_TTL_TG_4K;
case SZ_16K:
return TLBI_TTL_TG_16K;
case SZ_64K:
return TLBI_TTL_TG_64K;
default:
return 0;
}
}
#ifdef CONFIG_ARM64_ERRATUM_4193714
void sme_do_dvmsync(const struct cpumask *mask);
static inline void sme_dvmsync(struct mm_struct *mm)
{
if (!alternative_has_cap_unlikely(ARM64_WORKAROUND_4193714))
return;
sme_do_dvmsync(mm_cpumask(mm));
}
static inline void sme_dvmsync_add_pending(struct arch_tlbflush_unmap_batch *batch,
struct mm_struct *mm)
{
if (!alternative_has_cap_unlikely(ARM64_WORKAROUND_4193714))
return;
/*
* Order the mm_cpumask() read after the hardware DVMSync.
*/
dsb(ish);
if (cpumask_empty(mm_cpumask(mm)))
return;
/*
* Allocate the batch cpumask on first use. Fall back to an immediate
* IPI for this mm in case of failure.
*/
if (!cpumask_available(batch->cpumask) &&
!zalloc_cpumask_var(&batch->cpumask, GFP_ATOMIC)) {
sme_do_dvmsync(mm_cpumask(mm));
return;
}
cpumask_or(batch->cpumask, batch->cpumask, mm_cpumask(mm));
}
static inline void sme_dvmsync_batch(struct arch_tlbflush_unmap_batch *batch)
{
if (!alternative_has_cap_unlikely(ARM64_WORKAROUND_4193714))
return;
if (!cpumask_available(batch->cpumask))
return;
sme_do_dvmsync(batch->cpumask);
cpumask_clear(batch->cpumask);
}
#else
static inline void sme_dvmsync(struct mm_struct *mm)
{
}
static inline void sme_dvmsync_add_pending(struct arch_tlbflush_unmap_batch *batch,
struct mm_struct *mm)
{
}
static inline void sme_dvmsync_batch(struct arch_tlbflush_unmap_batch *batch)
{
}
#endif /* CONFIG_ARM64_ERRATUM_4193714 */
/*
* Level-based TLBI operations.
*
* When ARMv8.4-TTL exists, TLBI operations take an additional hint for
* the level at which the invalidation must take place. If the level is
* wrong, no invalidation may take place. In the case where the level
* cannot be easily determined, the value TLBI_TTL_UNKNOWN will perform
* a non-hinted invalidation. Any provided level outside the hint range
* will also cause fall-back to non-hinted invalidation.
*
* For Stage-2 invalidation, use the level values provided to that effect
* in asm/stage2_pgtable.h.
*/
#define TLBI_TTL_MASK GENMASK_ULL(47, 44)
#define TLBI_TTL_UNKNOWN INT_MAX
typedef void (*tlbi_op)(u64 arg);
static __always_inline void vae1is(u64 arg)
{
__tlbi(vae1is, arg);
__tlbi_user(vae1is, arg);
}
static __always_inline void vae2is(u64 arg)
{
__tlbi(vae2is, arg);
}
static __always_inline void vale1(u64 arg)
{
__tlbi(vale1, arg);
__tlbi_user(vale1, arg);
}
static __always_inline void vale1is(u64 arg)
{
__tlbi(vale1is, arg);
__tlbi_user(vale1is, arg);
}
static __always_inline void vale2is(u64 arg)
{
__tlbi(vale2is, arg);
}
static __always_inline void vaale1is(u64 arg)
{
__tlbi(vaale1is, arg);
}
static __always_inline void ipas2e1(u64 arg)
{
__tlbi(ipas2e1, arg);
}
static __always_inline void ipas2e1is(u64 arg)
{
__tlbi(ipas2e1is, arg);
}
static __always_inline void __tlbi_level_asid(tlbi_op op, u64 addr, u32 level,
u16 asid)
{
u64 arg = __TLBI_VADDR(addr, asid);
if (alternative_has_cap_unlikely(ARM64_HAS_ARMv8_4_TTL) && level <= 3) {
u64 ttl = level | (get_trans_granule() << 2);
FIELD_MODIFY(TLBI_TTL_MASK, &arg, ttl);
}
op(arg);
}
static inline void __tlbi_level(tlbi_op op, u64 addr, u32 level)
{
__tlbi_level_asid(op, addr, level, 0);
}
/*
* This macro creates a properly formatted VA operand for the TLB RANGE. The
* value bit assignments are:
*
* +----------+------+-------+-------+-------+----------------------+
* | ASID | TG | SCALE | NUM | TTL | BADDR |
* +-----------------+-------+-------+-------+----------------------+
* |63 48|47 46|45 44|43 39|38 37|36 0|
*
* The address range is determined by below formula: [BADDR, BADDR + (NUM + 1) *
* 2^(5*SCALE + 1) * PAGESIZE)
*
* Note that the first argument, baddr, is pre-shifted; If LPA2 is in use, BADDR
* holds addr[52:16]. Else BADDR holds page number. See for example ARM DDI
* 0487J.a section C5.5.60 "TLBI VAE1IS, TLBI VAE1ISNXS, TLB Invalidate by VA,
* EL1, Inner Shareable".
*
*/
#define TLBIR_ASID_MASK GENMASK_ULL(63, 48)
#define TLBIR_TG_MASK GENMASK_ULL(47, 46)
#define TLBIR_SCALE_MASK GENMASK_ULL(45, 44)
#define TLBIR_NUM_MASK GENMASK_ULL(43, 39)
#define TLBIR_TTL_MASK GENMASK_ULL(38, 37)
#define TLBIR_BADDR_MASK GENMASK_ULL(36, 0)
/* These macros are used by the TLBI RANGE feature. */
#define __TLBI_RANGE_PAGES(num, scale) \
((unsigned long)((num) + 1) << (5 * (scale) + 1))
#define MAX_TLBI_RANGE_PAGES __TLBI_RANGE_PAGES(31, 3)
/*
* Generate 'num' values from -1 to 31 with -1 rejected by the
* __flush_tlb_range() loop below. Its return value is only
* significant for a maximum of MAX_TLBI_RANGE_PAGES pages. If
* 'pages' is more than that, you must iterate over the overall
* range.
*/
#define __TLBI_RANGE_NUM(pages, scale) \
(((pages) >> (5 * (scale) + 1)) - 1)
#define __repeat_tlbi_sync(op, arg...) \
do { \
if (!alternative_has_cap_unlikely(ARM64_WORKAROUND_REPEAT_TLBI)) \
break; \
__tlbi(op, ##arg); \
dsb(ish); \
} while (0)
/*
* Complete broadcast TLB maintenance issued by the host which invalidates
* stage 1 information in the host's own translation regime.
*/
static inline void __tlbi_sync_s1ish(struct mm_struct *mm)
{
dsb(ish);
__repeat_tlbi_sync(vale1is, 0);
sme_dvmsync(mm);
}
static inline void __tlbi_sync_s1ish_batch(struct arch_tlbflush_unmap_batch *batch)
{
dsb(ish);
__repeat_tlbi_sync(vale1is, 0);
sme_dvmsync_batch(batch);
}
static inline void __tlbi_sync_s1ish_kernel(void)
{
dsb(ish);
__repeat_tlbi_sync(vale1is, 0);
}
/*
* Complete broadcast TLB maintenance issued by hyp code which invalidates
* stage 1 translation information in any translation regime.
*/
static inline void __tlbi_sync_s1ish_hyp(void)
{
dsb(ish);
__repeat_tlbi_sync(vale2is, 0);
}
/*
* TLB Invalidation
* ================
*
* This header file implements the low-level TLB invalidation routines
* (sometimes referred to as "flushing" in the kernel) for arm64.
*
* Every invalidation operation uses the following template:
*
* DSB ISHST // Ensure prior page-table updates have completed
* TLBI ... // Invalidate the TLB
* DSB ISH // Ensure the TLB invalidation has completed
* if (invalidated kernel mappings)
* ISB // Discard any instructions fetched from the old mapping
*
*
* The following functions form part of the "core" TLB invalidation API,
* as documented in Documentation/core-api/cachetlb.rst:
*
* flush_tlb_all()
* Invalidate the entire TLB (kernel + user) on all CPUs
*
* flush_tlb_mm(mm)
* Invalidate an entire user address space on all CPUs.
* The 'mm' argument identifies the ASID to invalidate.
*
* flush_tlb_range(vma, start, end)
* Invalidate the virtual-address range '[start, end)' on all
* CPUs for the user address space corresponding to 'vma->mm'.
* Note that this operation also invalidates any walk-cache
* entries associated with translations for the specified address
* range.
*
* flush_tlb_kernel_range(start, end)
* Same as flush_tlb_range(..., start, end), but applies to
* kernel mappings rather than a particular user address space.
* Whilst not explicitly documented, this function is used when
* unmapping pages from vmalloc/io space.
*
* flush_tlb_page(vma, addr)
* Equivalent to __flush_tlb_page(..., flags=TLBF_NONE)
*
*
* Next, we have some undocumented invalidation routines that you probably
* don't want to call unless you know what you're doing:
*
* local_flush_tlb_all()
* Same as flush_tlb_all(), but only applies to the calling CPU.
*
* __flush_tlb_kernel_pgtable(addr)
* Invalidate a single kernel mapping for address 'addr' on all
* CPUs, ensuring that any walk-cache entries associated with the
* translation are also invalidated.
*
* __flush_tlb_range(vma, start, end, stride, tlb_level, flags)
* Invalidate the virtual-address range '[start, end)' on all
* CPUs for the user address space corresponding to 'vma->mm'.
* The invalidation operations are issued at a granularity
* determined by 'stride'. tlb_level is the level at
* which the invalidation must take place. If the level is wrong,
* no invalidation may take place. In the case where the level
* cannot be easily determined, the value TLBI_TTL_UNKNOWN will
* perform a non-hinted invalidation. flags may be TLBF_NONE (0) or
* any combination of TLBF_NOWALKCACHE (elide eviction of walk
* cache entries), TLBF_NONOTIFY (don't call mmu notifiers),
* TLBF_NOSYNC (don't issue trailing dsb) and TLBF_NOBROADCAST
* (only perform the invalidation for the local cpu).
*
* __flush_tlb_page(vma, addr, flags)
* Invalidate a single user mapping for address 'addr' in the
* address space corresponding to 'vma->mm'. Note that this
* operation only invalidates a single level 3 page-table entry
* and therefore does not affect any walk-caches. flags may contain
* any combination of TLBF_NONOTIFY (don't call mmu notifiers),
* TLBF_NOSYNC (don't issue trailing dsb) and TLBF_NOBROADCAST
* (only perform the invalidation for the local cpu).
*
* Finally, take a look at asm/tlb.h to see how tlb_flush() is implemented
* on top of these routines, since that is our interface to the mmu_gather
* API as used by munmap() and friends.
*/
static inline void local_flush_tlb_all(void)
{
dsb(nshst);
__tlbi(vmalle1);
dsb(nsh);
isb();
}
static inline void flush_tlb_all(void)
{
dsb(ishst);
__tlbi(vmalle1is);
__tlbi_sync_s1ish_kernel();
isb();
}
static inline void flush_tlb_mm(struct mm_struct *mm)
{
unsigned long asid;
dsb(ishst);
asid = __TLBI_VADDR(0, ASID(mm));
__tlbi(aside1is, asid);
__tlbi_user(aside1is, asid);
__tlbi_sync_s1ish(mm);
mmu_notifier_arch_invalidate_secondary_tlbs(mm, 0, -1UL);
}
static inline bool arch_tlbbatch_should_defer(struct mm_struct *mm)
{
return true;
}
/*
* To support TLB batched flush for multiple pages unmapping, we only send
* the TLBI for each page in arch_tlbbatch_add_pending() and wait for the
* completion at the end in arch_tlbbatch_flush(). Since we've already issued
* TLBI for each page so only a DSB is needed to synchronise its effect on the
* other CPUs.
*
* This will save the time waiting on DSB comparing issuing a TLBI;DSB sequence
* for each page.
*/
static inline void arch_tlbbatch_flush(struct arch_tlbflush_unmap_batch *batch)
{
__tlbi_sync_s1ish_batch(batch);
}
/*
* This is meant to avoid soft lock-ups on large TLB flushing ranges and not
* necessarily a performance improvement.
*/
#define MAX_DVM_OPS PTRS_PER_PTE
/*
* __flush_tlb_range_op - Perform TLBI operation upon a range
*
* @lop: TLBI level operation to perform
* @rop: TLBI range operation to perform
* @start: The start address of the range
* @pages: Range as the number of pages from 'start'
* @stride: Flush granularity
* @asid: The ASID of the task (0 for IPA instructions)
* @level: Translation Table level hint, if known
* @lpa2: If 'true', the lpa2 scheme is used as set out below
*
* When the CPU does not support TLB range operations, flush the TLB
* entries one by one at the granularity of 'stride'. If the TLB
* range ops are supported, then:
*
* 1. If FEAT_LPA2 is in use, the start address of a range operation must be
* 64KB aligned, so flush pages one by one until the alignment is reached
* using the non-range operations. This step is skipped if LPA2 is not in
* use.
*
* 2. The minimum range granularity is decided by 'scale', so multiple range
* TLBI operations may be required. Start from scale = 3, flush the largest
* possible number of pages ((num+1)*2^(5*scale+1)) that fit into the
* requested range, then decrement scale and continue until one or zero pages
* are left. We must start from highest scale to ensure 64KB start alignment
* is maintained in the LPA2 case.
*
* 3. If there is 1 page remaining, flush it through non-range operations. Range
* operations can only span an even number of pages. We save this for last to
* ensure 64KB start alignment is maintained for the LPA2 case.
*/
static __always_inline void rvae1is(u64 arg)
{
__tlbi(rvae1is, arg);
__tlbi_user(rvae1is, arg);
}
static __always_inline void rvale1(u64 arg)
{
__tlbi(rvale1, arg);
__tlbi_user(rvale1, arg);
}
static __always_inline void rvale1is(u64 arg)
{
__tlbi(rvale1is, arg);
__tlbi_user(rvale1is, arg);
}
static __always_inline void rvaale1is(u64 arg)
{
__tlbi(rvaale1is, arg);
}
static __always_inline void ripas2e1is(u64 arg)
{
__tlbi(ripas2e1is, arg);
}
static __always_inline void __tlbi_range(tlbi_op op, u64 addr,
u16 asid, int scale, int num,
u32 level, bool lpa2)
{
u64 arg = 0;
arg |= FIELD_PREP(TLBIR_BADDR_MASK, addr >> (lpa2 ? 16 : PAGE_SHIFT));
arg |= FIELD_PREP(TLBIR_TTL_MASK, level > 3 ? 0 : level);
arg |= FIELD_PREP(TLBIR_NUM_MASK, num);
arg |= FIELD_PREP(TLBIR_SCALE_MASK, scale);
arg |= FIELD_PREP(TLBIR_TG_MASK, get_trans_granule());
arg |= FIELD_PREP(TLBIR_ASID_MASK, asid);
op(arg);
}
static __always_inline void __flush_tlb_range_op(tlbi_op lop, tlbi_op rop,
u64 start, size_t pages,
u64 stride, u16 asid,
u32 level, bool lpa2)
{
u64 addr = start, end = start + pages * PAGE_SIZE;
int scale = 3;
while (addr != end) {
int num;
pages = (end - addr) >> PAGE_SHIFT;
if (!system_supports_tlb_range() || pages == 1)
goto invalidate_one;
if (lpa2 && !IS_ALIGNED(addr, SZ_64K))
goto invalidate_one;
num = __TLBI_RANGE_NUM(pages, scale);
if (num >= 0) {
__tlbi_range(rop, addr, asid, scale, num, level, lpa2);
addr += __TLBI_RANGE_PAGES(num, scale) << PAGE_SHIFT;
}
scale--;
continue;
invalidate_one:
__tlbi_level_asid(lop, addr, level, asid);
addr += stride;
}
}
#define __flush_s1_tlb_range_op(op, start, pages, stride, asid, tlb_level) \
__flush_tlb_range_op(op, r##op, start, pages, stride, asid, tlb_level, lpa2_is_enabled())
#define __flush_s2_tlb_range_op(op, start, pages, stride, tlb_level) \
__flush_tlb_range_op(op, r##op, start, pages, stride, 0, tlb_level, kvm_lpa2_is_enabled())
static inline bool __flush_tlb_range_limit_excess(unsigned long pages,
unsigned long stride)
{
/*
* Assume that the worst case number of DVM ops required to flush a
* given range on a system that supports tlb-range is 20 (4 scales, 1
* final page, 15 for alignment on LPA2 systems), which is much smaller
* than MAX_DVM_OPS.
*/
if (system_supports_tlb_range())
return pages > MAX_TLBI_RANGE_PAGES;
return pages >= (MAX_DVM_OPS * stride) >> PAGE_SHIFT;
}
typedef unsigned __bitwise tlbf_t;
/* No special behaviour. */
#define TLBF_NONE ((__force tlbf_t)0)
/* Invalidate tlb entries only, leaving the page table walk cache intact. */
#define TLBF_NOWALKCACHE ((__force tlbf_t)BIT(0))
/* Skip the trailing dsb after issuing tlbi. */
#define TLBF_NOSYNC ((__force tlbf_t)BIT(1))
/* Suppress tlb notifier callbacks for this flush operation. */
#define TLBF_NONOTIFY ((__force tlbf_t)BIT(2))
/* Perform the tlbi locally without broadcasting to other CPUs. */
#define TLBF_NOBROADCAST ((__force tlbf_t)BIT(3))
static __always_inline void __do_flush_tlb_range(struct vm_area_struct *vma,
unsigned long start, unsigned long end,
unsigned long stride, int tlb_level,
tlbf_t flags)
{
struct mm_struct *mm = vma->vm_mm;
unsigned long asid, pages;
pages = (end - start) >> PAGE_SHIFT;
if (__flush_tlb_range_limit_excess(pages, stride)) {
flush_tlb_mm(mm);
return;
}
if (!(flags & TLBF_NOBROADCAST))
dsb(ishst);
else
dsb(nshst);
asid = ASID(mm);
switch (flags & (TLBF_NOWALKCACHE | TLBF_NOBROADCAST)) {
case TLBF_NONE:
__flush_s1_tlb_range_op(vae1is, start, pages, stride,
asid, tlb_level);
break;
case TLBF_NOWALKCACHE:
__flush_s1_tlb_range_op(vale1is, start, pages, stride,
asid, tlb_level);
break;
case TLBF_NOBROADCAST:
/* Combination unused */
BUG();
break;
case TLBF_NOWALKCACHE | TLBF_NOBROADCAST:
__flush_s1_tlb_range_op(vale1, start, pages, stride,
asid, tlb_level);
break;
}
if (!(flags & TLBF_NONOTIFY))
mmu_notifier_arch_invalidate_secondary_tlbs(mm, start, end);
if (!(flags & TLBF_NOSYNC)) {
if (!(flags & TLBF_NOBROADCAST))
__tlbi_sync_s1ish(mm);
else
dsb(nsh);
}
}
static inline void __flush_tlb_range(struct vm_area_struct *vma,
unsigned long start, unsigned long end,
unsigned long stride, int tlb_level,
tlbf_t flags)
{
start = round_down(start, stride);
end = round_up(end, stride);
__do_flush_tlb_range(vma, start, end, stride, tlb_level, flags);
}
static inline void flush_tlb_range(struct vm_area_struct *vma,
unsigned long start, unsigned long end)
{
/*
* We cannot use leaf-only invalidation here, since we may be invalidating
* table entries as part of collapsing hugepages or moving page tables.
* Set the tlb_level to TLBI_TTL_UNKNOWN because we can not get enough
* information here.
*/
__flush_tlb_range(vma, start, end, PAGE_SIZE, TLBI_TTL_UNKNOWN, TLBF_NONE);
}
static inline void __flush_tlb_page(struct vm_area_struct *vma,
unsigned long uaddr, tlbf_t flags)
{
unsigned long start = round_down(uaddr, PAGE_SIZE);
unsigned long end = start + PAGE_SIZE;
__do_flush_tlb_range(vma, start, end, PAGE_SIZE, 3,
TLBF_NOWALKCACHE | flags);
}
static inline void flush_tlb_page(struct vm_area_struct *vma,
unsigned long uaddr)
{
__flush_tlb_page(vma, uaddr, TLBF_NONE);
}
static inline void flush_tlb_kernel_range(unsigned long start, unsigned long end)
{
const unsigned long stride = PAGE_SIZE;
unsigned long pages;
start = round_down(start, stride);
end = round_up(end, stride);
pages = (end - start) >> PAGE_SHIFT;
if (__flush_tlb_range_limit_excess(pages, stride)) {
flush_tlb_all();
return;
}
dsb(ishst);
__flush_s1_tlb_range_op(vaale1is, start, pages, stride, 0,
TLBI_TTL_UNKNOWN);
__tlbi_sync_s1ish_kernel();
isb();
}
/*
* Used to invalidate the TLB (walk caches) corresponding to intermediate page
* table levels (pgd/pud/pmd).
*/
static inline void __flush_tlb_kernel_pgtable(unsigned long kaddr)
{
unsigned long addr = __TLBI_VADDR(kaddr, 0);
dsb(ishst);
__tlbi(vaae1is, addr);
__tlbi_sync_s1ish_kernel();
isb();
}
static inline void arch_tlbbatch_add_pending(struct arch_tlbflush_unmap_batch *batch,
struct mm_struct *mm, unsigned long start, unsigned long end)
{
struct vm_area_struct vma = { .vm_mm = mm, .vm_flags = 0 };
__flush_tlb_range(&vma, start, end, PAGE_SIZE, 3,
TLBF_NOWALKCACHE | TLBF_NOSYNC);
sme_dvmsync_add_pending(batch, mm);
}
static inline bool __pte_flags_need_flush(ptdesc_t oldval, ptdesc_t newval)
{
ptdesc_t diff = oldval ^ newval;
/* invalid to valid transition requires no flush */
if (!(oldval & PTE_VALID))
return false;
/* Transition in the SW bits requires no flush */
diff &= ~PTE_SWBITS_MASK;
return diff;
}
static inline bool pte_needs_flush(pte_t oldpte, pte_t newpte)
{
return __pte_flags_need_flush(pte_val(oldpte), pte_val(newpte));
}
#define pte_needs_flush pte_needs_flush
static inline bool huge_pmd_needs_flush(pmd_t oldpmd, pmd_t newpmd)
{
return __pte_flags_need_flush(pmd_val(oldpmd), pmd_val(newpmd));
}
#define huge_pmd_needs_flush huge_pmd_needs_flush
#undef __tlbi_user
#undef __TLBI_VADDR
#endif
#endif