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-rw-r--r--arch/powerpc/mm/book3s64/radix_tlb.c1285
1 files changed, 1285 insertions, 0 deletions
diff --git a/arch/powerpc/mm/book3s64/radix_tlb.c b/arch/powerpc/mm/book3s64/radix_tlb.c
new file mode 100644
index 000000000..abbfd5cc4
--- /dev/null
+++ b/arch/powerpc/mm/book3s64/radix_tlb.c
@@ -0,0 +1,1285 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * TLB flush routines for radix kernels.
+ *
+ * Copyright 2015-2016, Aneesh Kumar K.V, IBM Corporation.
+ */
+
+#include <linux/mm.h>
+#include <linux/hugetlb.h>
+#include <linux/memblock.h>
+#include <linux/mmu_context.h>
+#include <linux/sched/mm.h>
+
+#include <asm/ppc-opcode.h>
+#include <asm/tlb.h>
+#include <asm/tlbflush.h>
+#include <asm/trace.h>
+#include <asm/cputhreads.h>
+#include <asm/plpar_wrappers.h>
+
+#define RIC_FLUSH_TLB 0
+#define RIC_FLUSH_PWC 1
+#define RIC_FLUSH_ALL 2
+
+/*
+ * tlbiel instruction for radix, set invalidation
+ * i.e., r=1 and is=01 or is=10 or is=11
+ */
+static __always_inline void tlbiel_radix_set_isa300(unsigned int set, unsigned int is,
+ unsigned int pid,
+ unsigned int ric, unsigned int prs)
+{
+ unsigned long rb;
+ unsigned long rs;
+
+ rb = (set << PPC_BITLSHIFT(51)) | (is << PPC_BITLSHIFT(53));
+ rs = ((unsigned long)pid << PPC_BITLSHIFT(31));
+
+ asm volatile(PPC_TLBIEL(%0, %1, %2, %3, 1)
+ : : "r"(rb), "r"(rs), "i"(ric), "i"(prs)
+ : "memory");
+}
+
+static void tlbiel_all_isa300(unsigned int num_sets, unsigned int is)
+{
+ unsigned int set;
+
+ asm volatile("ptesync": : :"memory");
+
+ /*
+ * Flush the first set of the TLB, and the entire Page Walk Cache
+ * and partition table entries. Then flush the remaining sets of the
+ * TLB.
+ */
+
+ if (early_cpu_has_feature(CPU_FTR_HVMODE)) {
+ /* MSR[HV] should flush partition scope translations first. */
+ tlbiel_radix_set_isa300(0, is, 0, RIC_FLUSH_ALL, 0);
+ for (set = 1; set < num_sets; set++)
+ tlbiel_radix_set_isa300(set, is, 0, RIC_FLUSH_TLB, 0);
+ }
+
+ /* Flush process scoped entries. */
+ tlbiel_radix_set_isa300(0, is, 0, RIC_FLUSH_ALL, 1);
+ for (set = 1; set < num_sets; set++)
+ tlbiel_radix_set_isa300(set, is, 0, RIC_FLUSH_TLB, 1);
+
+ ppc_after_tlbiel_barrier();
+}
+
+void radix__tlbiel_all(unsigned int action)
+{
+ unsigned int is;
+
+ switch (action) {
+ case TLB_INVAL_SCOPE_GLOBAL:
+ is = 3;
+ break;
+ case TLB_INVAL_SCOPE_LPID:
+ is = 2;
+ break;
+ default:
+ BUG();
+ }
+
+ if (early_cpu_has_feature(CPU_FTR_ARCH_300))
+ tlbiel_all_isa300(POWER9_TLB_SETS_RADIX, is);
+ else
+ WARN(1, "%s called on pre-POWER9 CPU\n", __func__);
+
+ asm volatile(PPC_ISA_3_0_INVALIDATE_ERAT "; isync" : : :"memory");
+}
+
+static __always_inline void __tlbiel_pid(unsigned long pid, int set,
+ unsigned long ric)
+{
+ unsigned long rb,rs,prs,r;
+
+ rb = PPC_BIT(53); /* IS = 1 */
+ rb |= set << PPC_BITLSHIFT(51);
+ rs = ((unsigned long)pid) << PPC_BITLSHIFT(31);
+ prs = 1; /* process scoped */
+ r = 1; /* radix format */
+
+ asm volatile(PPC_TLBIEL(%0, %4, %3, %2, %1)
+ : : "r"(rb), "i"(r), "i"(prs), "i"(ric), "r"(rs) : "memory");
+ trace_tlbie(0, 1, rb, rs, ric, prs, r);
+}
+
+static __always_inline void __tlbie_pid(unsigned long pid, unsigned long ric)
+{
+ unsigned long rb,rs,prs,r;
+
+ rb = PPC_BIT(53); /* IS = 1 */
+ rs = pid << PPC_BITLSHIFT(31);
+ prs = 1; /* process scoped */
+ r = 1; /* radix format */
+
+ asm volatile(PPC_TLBIE_5(%0, %4, %3, %2, %1)
+ : : "r"(rb), "i"(r), "i"(prs), "i"(ric), "r"(rs) : "memory");
+ trace_tlbie(0, 0, rb, rs, ric, prs, r);
+}
+
+static __always_inline void __tlbie_lpid(unsigned long lpid, unsigned long ric)
+{
+ unsigned long rb,rs,prs,r;
+
+ rb = PPC_BIT(52); /* IS = 2 */
+ rs = lpid;
+ prs = 0; /* partition scoped */
+ r = 1; /* radix format */
+
+ asm volatile(PPC_TLBIE_5(%0, %4, %3, %2, %1)
+ : : "r"(rb), "i"(r), "i"(prs), "i"(ric), "r"(rs) : "memory");
+ trace_tlbie(lpid, 0, rb, rs, ric, prs, r);
+}
+
+static __always_inline void __tlbie_lpid_guest(unsigned long lpid, unsigned long ric)
+{
+ unsigned long rb,rs,prs,r;
+
+ rb = PPC_BIT(52); /* IS = 2 */
+ rs = lpid;
+ prs = 1; /* process scoped */
+ r = 1; /* radix format */
+
+ asm volatile(PPC_TLBIE_5(%0, %4, %3, %2, %1)
+ : : "r"(rb), "i"(r), "i"(prs), "i"(ric), "r"(rs) : "memory");
+ trace_tlbie(lpid, 0, rb, rs, ric, prs, r);
+}
+
+static __always_inline void __tlbiel_va(unsigned long va, unsigned long pid,
+ unsigned long ap, unsigned long ric)
+{
+ unsigned long rb,rs,prs,r;
+
+ rb = va & ~(PPC_BITMASK(52, 63));
+ rb |= ap << PPC_BITLSHIFT(58);
+ rs = pid << PPC_BITLSHIFT(31);
+ prs = 1; /* process scoped */
+ r = 1; /* radix format */
+
+ asm volatile(PPC_TLBIEL(%0, %4, %3, %2, %1)
+ : : "r"(rb), "i"(r), "i"(prs), "i"(ric), "r"(rs) : "memory");
+ trace_tlbie(0, 1, rb, rs, ric, prs, r);
+}
+
+static __always_inline void __tlbie_va(unsigned long va, unsigned long pid,
+ unsigned long ap, unsigned long ric)
+{
+ unsigned long rb,rs,prs,r;
+
+ rb = va & ~(PPC_BITMASK(52, 63));
+ rb |= ap << PPC_BITLSHIFT(58);
+ rs = pid << PPC_BITLSHIFT(31);
+ prs = 1; /* process scoped */
+ r = 1; /* radix format */
+
+ asm volatile(PPC_TLBIE_5(%0, %4, %3, %2, %1)
+ : : "r"(rb), "i"(r), "i"(prs), "i"(ric), "r"(rs) : "memory");
+ trace_tlbie(0, 0, rb, rs, ric, prs, r);
+}
+
+static __always_inline void __tlbie_lpid_va(unsigned long va, unsigned long lpid,
+ unsigned long ap, unsigned long ric)
+{
+ unsigned long rb,rs,prs,r;
+
+ rb = va & ~(PPC_BITMASK(52, 63));
+ rb |= ap << PPC_BITLSHIFT(58);
+ rs = lpid;
+ prs = 0; /* partition scoped */
+ r = 1; /* radix format */
+
+ asm volatile(PPC_TLBIE_5(%0, %4, %3, %2, %1)
+ : : "r"(rb), "i"(r), "i"(prs), "i"(ric), "r"(rs) : "memory");
+ trace_tlbie(lpid, 0, rb, rs, ric, prs, r);
+}
+
+
+static inline void fixup_tlbie_va(unsigned long va, unsigned long pid,
+ unsigned long ap)
+{
+ if (cpu_has_feature(CPU_FTR_P9_TLBIE_ERAT_BUG)) {
+ asm volatile("ptesync": : :"memory");
+ __tlbie_va(va, 0, ap, RIC_FLUSH_TLB);
+ }
+
+ if (cpu_has_feature(CPU_FTR_P9_TLBIE_STQ_BUG)) {
+ asm volatile("ptesync": : :"memory");
+ __tlbie_va(va, pid, ap, RIC_FLUSH_TLB);
+ }
+}
+
+static inline void fixup_tlbie_va_range(unsigned long va, unsigned long pid,
+ unsigned long ap)
+{
+ if (cpu_has_feature(CPU_FTR_P9_TLBIE_ERAT_BUG)) {
+ asm volatile("ptesync": : :"memory");
+ __tlbie_pid(0, RIC_FLUSH_TLB);
+ }
+
+ if (cpu_has_feature(CPU_FTR_P9_TLBIE_STQ_BUG)) {
+ asm volatile("ptesync": : :"memory");
+ __tlbie_va(va, pid, ap, RIC_FLUSH_TLB);
+ }
+}
+
+static inline void fixup_tlbie_pid(unsigned long pid)
+{
+ /*
+ * We can use any address for the invalidation, pick one which is
+ * probably unused as an optimisation.
+ */
+ unsigned long va = ((1UL << 52) - 1);
+
+ if (cpu_has_feature(CPU_FTR_P9_TLBIE_ERAT_BUG)) {
+ asm volatile("ptesync": : :"memory");
+ __tlbie_pid(0, RIC_FLUSH_TLB);
+ }
+
+ if (cpu_has_feature(CPU_FTR_P9_TLBIE_STQ_BUG)) {
+ asm volatile("ptesync": : :"memory");
+ __tlbie_va(va, pid, mmu_get_ap(MMU_PAGE_64K), RIC_FLUSH_TLB);
+ }
+}
+
+
+static inline void fixup_tlbie_lpid_va(unsigned long va, unsigned long lpid,
+ unsigned long ap)
+{
+ if (cpu_has_feature(CPU_FTR_P9_TLBIE_ERAT_BUG)) {
+ asm volatile("ptesync": : :"memory");
+ __tlbie_lpid_va(va, 0, ap, RIC_FLUSH_TLB);
+ }
+
+ if (cpu_has_feature(CPU_FTR_P9_TLBIE_STQ_BUG)) {
+ asm volatile("ptesync": : :"memory");
+ __tlbie_lpid_va(va, lpid, ap, RIC_FLUSH_TLB);
+ }
+}
+
+static inline void fixup_tlbie_lpid(unsigned long lpid)
+{
+ /*
+ * We can use any address for the invalidation, pick one which is
+ * probably unused as an optimisation.
+ */
+ unsigned long va = ((1UL << 52) - 1);
+
+ if (cpu_has_feature(CPU_FTR_P9_TLBIE_ERAT_BUG)) {
+ asm volatile("ptesync": : :"memory");
+ __tlbie_lpid(0, RIC_FLUSH_TLB);
+ }
+
+ if (cpu_has_feature(CPU_FTR_P9_TLBIE_STQ_BUG)) {
+ asm volatile("ptesync": : :"memory");
+ __tlbie_lpid_va(va, lpid, mmu_get_ap(MMU_PAGE_64K), RIC_FLUSH_TLB);
+ }
+}
+
+/*
+ * We use 128 set in radix mode and 256 set in hpt mode.
+ */
+static inline void _tlbiel_pid(unsigned long pid, unsigned long ric)
+{
+ int set;
+
+ asm volatile("ptesync": : :"memory");
+
+ switch (ric) {
+ case RIC_FLUSH_PWC:
+
+ /* For PWC, only one flush is needed */
+ __tlbiel_pid(pid, 0, RIC_FLUSH_PWC);
+ ppc_after_tlbiel_barrier();
+ return;
+ case RIC_FLUSH_TLB:
+ __tlbiel_pid(pid, 0, RIC_FLUSH_TLB);
+ break;
+ case RIC_FLUSH_ALL:
+ default:
+ /*
+ * Flush the first set of the TLB, and if
+ * we're doing a RIC_FLUSH_ALL, also flush
+ * the entire Page Walk Cache.
+ */
+ __tlbiel_pid(pid, 0, RIC_FLUSH_ALL);
+ }
+
+ /* For the remaining sets, just flush the TLB */
+ for (set = 1; set < POWER9_TLB_SETS_RADIX ; set++)
+ __tlbiel_pid(pid, set, RIC_FLUSH_TLB);
+
+ ppc_after_tlbiel_barrier();
+ asm volatile(PPC_RADIX_INVALIDATE_ERAT_USER "; isync" : : :"memory");
+}
+
+static inline void _tlbie_pid(unsigned long pid, unsigned long ric)
+{
+ asm volatile("ptesync": : :"memory");
+
+ /*
+ * Workaround the fact that the "ric" argument to __tlbie_pid
+ * must be a compile-time contraint to match the "i" constraint
+ * in the asm statement.
+ */
+ switch (ric) {
+ case RIC_FLUSH_TLB:
+ __tlbie_pid(pid, RIC_FLUSH_TLB);
+ fixup_tlbie_pid(pid);
+ break;
+ case RIC_FLUSH_PWC:
+ __tlbie_pid(pid, RIC_FLUSH_PWC);
+ break;
+ case RIC_FLUSH_ALL:
+ default:
+ __tlbie_pid(pid, RIC_FLUSH_ALL);
+ fixup_tlbie_pid(pid);
+ }
+ asm volatile("eieio; tlbsync; ptesync": : :"memory");
+}
+
+struct tlbiel_pid {
+ unsigned long pid;
+ unsigned long ric;
+};
+
+static void do_tlbiel_pid(void *info)
+{
+ struct tlbiel_pid *t = info;
+
+ if (t->ric == RIC_FLUSH_TLB)
+ _tlbiel_pid(t->pid, RIC_FLUSH_TLB);
+ else if (t->ric == RIC_FLUSH_PWC)
+ _tlbiel_pid(t->pid, RIC_FLUSH_PWC);
+ else
+ _tlbiel_pid(t->pid, RIC_FLUSH_ALL);
+}
+
+static inline void _tlbiel_pid_multicast(struct mm_struct *mm,
+ unsigned long pid, unsigned long ric)
+{
+ struct cpumask *cpus = mm_cpumask(mm);
+ struct tlbiel_pid t = { .pid = pid, .ric = ric };
+
+ on_each_cpu_mask(cpus, do_tlbiel_pid, &t, 1);
+ /*
+ * Always want the CPU translations to be invalidated with tlbiel in
+ * these paths, so while coprocessors must use tlbie, we can not
+ * optimise away the tlbiel component.
+ */
+ if (atomic_read(&mm->context.copros) > 0)
+ _tlbie_pid(pid, RIC_FLUSH_ALL);
+}
+
+static inline void _tlbie_lpid(unsigned long lpid, unsigned long ric)
+{
+ asm volatile("ptesync": : :"memory");
+
+ /*
+ * Workaround the fact that the "ric" argument to __tlbie_pid
+ * must be a compile-time contraint to match the "i" constraint
+ * in the asm statement.
+ */
+ switch (ric) {
+ case RIC_FLUSH_TLB:
+ __tlbie_lpid(lpid, RIC_FLUSH_TLB);
+ fixup_tlbie_lpid(lpid);
+ break;
+ case RIC_FLUSH_PWC:
+ __tlbie_lpid(lpid, RIC_FLUSH_PWC);
+ break;
+ case RIC_FLUSH_ALL:
+ default:
+ __tlbie_lpid(lpid, RIC_FLUSH_ALL);
+ fixup_tlbie_lpid(lpid);
+ }
+ asm volatile("eieio; tlbsync; ptesync": : :"memory");
+}
+
+static __always_inline void _tlbie_lpid_guest(unsigned long lpid, unsigned long ric)
+{
+ /*
+ * Workaround the fact that the "ric" argument to __tlbie_pid
+ * must be a compile-time contraint to match the "i" constraint
+ * in the asm statement.
+ */
+ switch (ric) {
+ case RIC_FLUSH_TLB:
+ __tlbie_lpid_guest(lpid, RIC_FLUSH_TLB);
+ break;
+ case RIC_FLUSH_PWC:
+ __tlbie_lpid_guest(lpid, RIC_FLUSH_PWC);
+ break;
+ case RIC_FLUSH_ALL:
+ default:
+ __tlbie_lpid_guest(lpid, RIC_FLUSH_ALL);
+ }
+ fixup_tlbie_lpid(lpid);
+ asm volatile("eieio; tlbsync; ptesync": : :"memory");
+}
+
+static inline void __tlbiel_va_range(unsigned long start, unsigned long end,
+ unsigned long pid, unsigned long page_size,
+ unsigned long psize)
+{
+ unsigned long addr;
+ unsigned long ap = mmu_get_ap(psize);
+
+ for (addr = start; addr < end; addr += page_size)
+ __tlbiel_va(addr, pid, ap, RIC_FLUSH_TLB);
+}
+
+static __always_inline void _tlbiel_va(unsigned long va, unsigned long pid,
+ unsigned long psize, unsigned long ric)
+{
+ unsigned long ap = mmu_get_ap(psize);
+
+ asm volatile("ptesync": : :"memory");
+ __tlbiel_va(va, pid, ap, ric);
+ ppc_after_tlbiel_barrier();
+}
+
+static inline void _tlbiel_va_range(unsigned long start, unsigned long end,
+ unsigned long pid, unsigned long page_size,
+ unsigned long psize, bool also_pwc)
+{
+ asm volatile("ptesync": : :"memory");
+ if (also_pwc)
+ __tlbiel_pid(pid, 0, RIC_FLUSH_PWC);
+ __tlbiel_va_range(start, end, pid, page_size, psize);
+ ppc_after_tlbiel_barrier();
+}
+
+static inline void __tlbie_va_range(unsigned long start, unsigned long end,
+ unsigned long pid, unsigned long page_size,
+ unsigned long psize)
+{
+ unsigned long addr;
+ unsigned long ap = mmu_get_ap(psize);
+
+ for (addr = start; addr < end; addr += page_size)
+ __tlbie_va(addr, pid, ap, RIC_FLUSH_TLB);
+
+ fixup_tlbie_va_range(addr - page_size, pid, ap);
+}
+
+static __always_inline void _tlbie_va(unsigned long va, unsigned long pid,
+ unsigned long psize, unsigned long ric)
+{
+ unsigned long ap = mmu_get_ap(psize);
+
+ asm volatile("ptesync": : :"memory");
+ __tlbie_va(va, pid, ap, ric);
+ fixup_tlbie_va(va, pid, ap);
+ asm volatile("eieio; tlbsync; ptesync": : :"memory");
+}
+
+struct tlbiel_va {
+ unsigned long pid;
+ unsigned long va;
+ unsigned long psize;
+ unsigned long ric;
+};
+
+static void do_tlbiel_va(void *info)
+{
+ struct tlbiel_va *t = info;
+
+ if (t->ric == RIC_FLUSH_TLB)
+ _tlbiel_va(t->va, t->pid, t->psize, RIC_FLUSH_TLB);
+ else if (t->ric == RIC_FLUSH_PWC)
+ _tlbiel_va(t->va, t->pid, t->psize, RIC_FLUSH_PWC);
+ else
+ _tlbiel_va(t->va, t->pid, t->psize, RIC_FLUSH_ALL);
+}
+
+static inline void _tlbiel_va_multicast(struct mm_struct *mm,
+ unsigned long va, unsigned long pid,
+ unsigned long psize, unsigned long ric)
+{
+ struct cpumask *cpus = mm_cpumask(mm);
+ struct tlbiel_va t = { .va = va, .pid = pid, .psize = psize, .ric = ric };
+ on_each_cpu_mask(cpus, do_tlbiel_va, &t, 1);
+ if (atomic_read(&mm->context.copros) > 0)
+ _tlbie_va(va, pid, psize, RIC_FLUSH_TLB);
+}
+
+struct tlbiel_va_range {
+ unsigned long pid;
+ unsigned long start;
+ unsigned long end;
+ unsigned long page_size;
+ unsigned long psize;
+ bool also_pwc;
+};
+
+static void do_tlbiel_va_range(void *info)
+{
+ struct tlbiel_va_range *t = info;
+
+ _tlbiel_va_range(t->start, t->end, t->pid, t->page_size,
+ t->psize, t->also_pwc);
+}
+
+static __always_inline void _tlbie_lpid_va(unsigned long va, unsigned long lpid,
+ unsigned long psize, unsigned long ric)
+{
+ unsigned long ap = mmu_get_ap(psize);
+
+ asm volatile("ptesync": : :"memory");
+ __tlbie_lpid_va(va, lpid, ap, ric);
+ fixup_tlbie_lpid_va(va, lpid, ap);
+ asm volatile("eieio; tlbsync; ptesync": : :"memory");
+}
+
+static inline void _tlbie_va_range(unsigned long start, unsigned long end,
+ unsigned long pid, unsigned long page_size,
+ unsigned long psize, bool also_pwc)
+{
+ asm volatile("ptesync": : :"memory");
+ if (also_pwc)
+ __tlbie_pid(pid, RIC_FLUSH_PWC);
+ __tlbie_va_range(start, end, pid, page_size, psize);
+ asm volatile("eieio; tlbsync; ptesync": : :"memory");
+}
+
+static inline void _tlbiel_va_range_multicast(struct mm_struct *mm,
+ unsigned long start, unsigned long end,
+ unsigned long pid, unsigned long page_size,
+ unsigned long psize, bool also_pwc)
+{
+ struct cpumask *cpus = mm_cpumask(mm);
+ struct tlbiel_va_range t = { .start = start, .end = end,
+ .pid = pid, .page_size = page_size,
+ .psize = psize, .also_pwc = also_pwc };
+
+ on_each_cpu_mask(cpus, do_tlbiel_va_range, &t, 1);
+ if (atomic_read(&mm->context.copros) > 0)
+ _tlbie_va_range(start, end, pid, page_size, psize, also_pwc);
+}
+
+/*
+ * Base TLB flushing operations:
+ *
+ * - 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 kernel pages
+ *
+ * - local_* variants of page and mm only apply to the current
+ * processor
+ */
+void radix__local_flush_tlb_mm(struct mm_struct *mm)
+{
+ unsigned long pid;
+
+ preempt_disable();
+ pid = mm->context.id;
+ if (pid != MMU_NO_CONTEXT)
+ _tlbiel_pid(pid, RIC_FLUSH_TLB);
+ preempt_enable();
+}
+EXPORT_SYMBOL(radix__local_flush_tlb_mm);
+
+#ifndef CONFIG_SMP
+void radix__local_flush_all_mm(struct mm_struct *mm)
+{
+ unsigned long pid;
+
+ preempt_disable();
+ pid = mm->context.id;
+ if (pid != MMU_NO_CONTEXT)
+ _tlbiel_pid(pid, RIC_FLUSH_ALL);
+ preempt_enable();
+}
+EXPORT_SYMBOL(radix__local_flush_all_mm);
+
+static void __flush_all_mm(struct mm_struct *mm, bool fullmm)
+{
+ radix__local_flush_all_mm(mm);
+}
+#endif /* CONFIG_SMP */
+
+void radix__local_flush_tlb_page_psize(struct mm_struct *mm, unsigned long vmaddr,
+ int psize)
+{
+ unsigned long pid;
+
+ preempt_disable();
+ pid = mm->context.id;
+ if (pid != MMU_NO_CONTEXT)
+ _tlbiel_va(vmaddr, pid, psize, RIC_FLUSH_TLB);
+ preempt_enable();
+}
+
+void radix__local_flush_tlb_page(struct vm_area_struct *vma, unsigned long vmaddr)
+{
+#ifdef CONFIG_HUGETLB_PAGE
+ /* need the return fix for nohash.c */
+ if (is_vm_hugetlb_page(vma))
+ return radix__local_flush_hugetlb_page(vma, vmaddr);
+#endif
+ radix__local_flush_tlb_page_psize(vma->vm_mm, vmaddr, mmu_virtual_psize);
+}
+EXPORT_SYMBOL(radix__local_flush_tlb_page);
+
+static bool mm_is_singlethreaded(struct mm_struct *mm)
+{
+ if (atomic_read(&mm->context.copros) > 0)
+ return false;
+ if (atomic_read(&mm->mm_users) <= 1 && current->mm == mm)
+ return true;
+ return false;
+}
+
+static bool mm_needs_flush_escalation(struct mm_struct *mm)
+{
+ /*
+ * P9 nest MMU has issues with the page walk cache
+ * caching PTEs and not flushing them properly when
+ * RIC = 0 for a PID/LPID invalidate
+ */
+ if (atomic_read(&mm->context.copros) > 0)
+ return true;
+ return false;
+}
+
+#ifdef CONFIG_SMP
+static void do_exit_flush_lazy_tlb(void *arg)
+{
+ struct mm_struct *mm = arg;
+ unsigned long pid = mm->context.id;
+
+ /*
+ * A kthread could have done a mmget_not_zero() after the flushing CPU
+ * checked mm_is_singlethreaded, and be in the process of
+ * kthread_use_mm when interrupted here. In that case, current->mm will
+ * be set to mm, because kthread_use_mm() setting ->mm and switching to
+ * the mm is done with interrupts off.
+ */
+ if (current->mm == mm)
+ goto out_flush;
+
+ if (current->active_mm == mm) {
+ WARN_ON_ONCE(current->mm != NULL);
+ /* Is a kernel thread and is using mm as the lazy tlb */
+ mmgrab(&init_mm);
+ current->active_mm = &init_mm;
+ switch_mm_irqs_off(mm, &init_mm, current);
+ mmdrop(mm);
+ }
+
+ atomic_dec(&mm->context.active_cpus);
+ cpumask_clear_cpu(smp_processor_id(), mm_cpumask(mm));
+
+out_flush:
+ _tlbiel_pid(pid, RIC_FLUSH_ALL);
+}
+
+static void exit_flush_lazy_tlbs(struct mm_struct *mm)
+{
+ /*
+ * Would be nice if this was async so it could be run in
+ * parallel with our local flush, but generic code does not
+ * give a good API for it. Could extend the generic code or
+ * make a special powerpc IPI for flushing TLBs.
+ * For now it's not too performance critical.
+ */
+ smp_call_function_many(mm_cpumask(mm), do_exit_flush_lazy_tlb,
+ (void *)mm, 1);
+}
+
+void radix__flush_tlb_mm(struct mm_struct *mm)
+{
+ unsigned long pid;
+
+ pid = mm->context.id;
+ if (unlikely(pid == MMU_NO_CONTEXT))
+ return;
+
+ preempt_disable();
+ /*
+ * Order loads of mm_cpumask vs previous stores to clear ptes before
+ * the invalidate. See barrier in switch_mm_irqs_off
+ */
+ smp_mb();
+ if (!mm_is_thread_local(mm)) {
+ if (unlikely(mm_is_singlethreaded(mm))) {
+ exit_flush_lazy_tlbs(mm);
+ goto local;
+ }
+
+ if (!mmu_has_feature(MMU_FTR_GTSE)) {
+ unsigned long tgt = H_RPTI_TARGET_CMMU;
+
+ if (atomic_read(&mm->context.copros) > 0)
+ tgt |= H_RPTI_TARGET_NMMU;
+ pseries_rpt_invalidate(pid, tgt, H_RPTI_TYPE_TLB,
+ H_RPTI_PAGE_ALL, 0, -1UL);
+ } else if (cputlb_use_tlbie()) {
+ if (mm_needs_flush_escalation(mm))
+ _tlbie_pid(pid, RIC_FLUSH_ALL);
+ else
+ _tlbie_pid(pid, RIC_FLUSH_TLB);
+ } else {
+ _tlbiel_pid_multicast(mm, pid, RIC_FLUSH_TLB);
+ }
+ } else {
+local:
+ _tlbiel_pid(pid, RIC_FLUSH_TLB);
+ }
+ preempt_enable();
+}
+EXPORT_SYMBOL(radix__flush_tlb_mm);
+
+static void __flush_all_mm(struct mm_struct *mm, bool fullmm)
+{
+ unsigned long pid;
+
+ pid = mm->context.id;
+ if (unlikely(pid == MMU_NO_CONTEXT))
+ return;
+
+ preempt_disable();
+ smp_mb(); /* see radix__flush_tlb_mm */
+ if (!mm_is_thread_local(mm)) {
+ if (unlikely(mm_is_singlethreaded(mm))) {
+ if (!fullmm) {
+ exit_flush_lazy_tlbs(mm);
+ goto local;
+ }
+ }
+ if (!mmu_has_feature(MMU_FTR_GTSE)) {
+ unsigned long tgt = H_RPTI_TARGET_CMMU;
+ unsigned long type = H_RPTI_TYPE_TLB | H_RPTI_TYPE_PWC |
+ H_RPTI_TYPE_PRT;
+
+ if (atomic_read(&mm->context.copros) > 0)
+ tgt |= H_RPTI_TARGET_NMMU;
+ pseries_rpt_invalidate(pid, tgt, type,
+ H_RPTI_PAGE_ALL, 0, -1UL);
+ } else if (cputlb_use_tlbie())
+ _tlbie_pid(pid, RIC_FLUSH_ALL);
+ else
+ _tlbiel_pid_multicast(mm, pid, RIC_FLUSH_ALL);
+ } else {
+local:
+ _tlbiel_pid(pid, RIC_FLUSH_ALL);
+ }
+ preempt_enable();
+}
+
+void radix__flush_all_mm(struct mm_struct *mm)
+{
+ __flush_all_mm(mm, false);
+}
+EXPORT_SYMBOL(radix__flush_all_mm);
+
+void radix__flush_tlb_page_psize(struct mm_struct *mm, unsigned long vmaddr,
+ int psize)
+{
+ unsigned long pid;
+
+ pid = mm->context.id;
+ if (unlikely(pid == MMU_NO_CONTEXT))
+ return;
+
+ preempt_disable();
+ smp_mb(); /* see radix__flush_tlb_mm */
+ if (!mm_is_thread_local(mm)) {
+ if (unlikely(mm_is_singlethreaded(mm))) {
+ exit_flush_lazy_tlbs(mm);
+ goto local;
+ }
+ if (!mmu_has_feature(MMU_FTR_GTSE)) {
+ unsigned long tgt, pg_sizes, size;
+
+ tgt = H_RPTI_TARGET_CMMU;
+ pg_sizes = psize_to_rpti_pgsize(psize);
+ size = 1UL << mmu_psize_to_shift(psize);
+
+ if (atomic_read(&mm->context.copros) > 0)
+ tgt |= H_RPTI_TARGET_NMMU;
+ pseries_rpt_invalidate(pid, tgt, H_RPTI_TYPE_TLB,
+ pg_sizes, vmaddr,
+ vmaddr + size);
+ } else if (cputlb_use_tlbie())
+ _tlbie_va(vmaddr, pid, psize, RIC_FLUSH_TLB);
+ else
+ _tlbiel_va_multicast(mm, vmaddr, pid, psize, RIC_FLUSH_TLB);
+ } else {
+local:
+ _tlbiel_va(vmaddr, pid, psize, RIC_FLUSH_TLB);
+ }
+ preempt_enable();
+}
+
+void radix__flush_tlb_page(struct vm_area_struct *vma, unsigned long vmaddr)
+{
+#ifdef CONFIG_HUGETLB_PAGE
+ if (is_vm_hugetlb_page(vma))
+ return radix__flush_hugetlb_page(vma, vmaddr);
+#endif
+ radix__flush_tlb_page_psize(vma->vm_mm, vmaddr, mmu_virtual_psize);
+}
+EXPORT_SYMBOL(radix__flush_tlb_page);
+
+#else /* CONFIG_SMP */
+static inline void exit_flush_lazy_tlbs(struct mm_struct *mm) { }
+#endif /* CONFIG_SMP */
+
+static void do_tlbiel_kernel(void *info)
+{
+ _tlbiel_pid(0, RIC_FLUSH_ALL);
+}
+
+static inline void _tlbiel_kernel_broadcast(void)
+{
+ on_each_cpu(do_tlbiel_kernel, NULL, 1);
+ if (tlbie_capable) {
+ /*
+ * Coherent accelerators don't refcount kernel memory mappings,
+ * so have to always issue a tlbie for them. This is quite a
+ * slow path anyway.
+ */
+ _tlbie_pid(0, RIC_FLUSH_ALL);
+ }
+}
+
+/*
+ * If kernel TLBIs ever become local rather than global, then
+ * drivers/misc/ocxl/link.c:ocxl_link_add_pe will need some work, as it
+ * assumes kernel TLBIs are global.
+ */
+void radix__flush_tlb_kernel_range(unsigned long start, unsigned long end)
+{
+ if (!mmu_has_feature(MMU_FTR_GTSE)) {
+ unsigned long tgt = H_RPTI_TARGET_CMMU | H_RPTI_TARGET_NMMU;
+ unsigned long type = H_RPTI_TYPE_TLB | H_RPTI_TYPE_PWC |
+ H_RPTI_TYPE_PRT;
+
+ pseries_rpt_invalidate(0, tgt, type, H_RPTI_PAGE_ALL,
+ start, end);
+ } else if (cputlb_use_tlbie())
+ _tlbie_pid(0, RIC_FLUSH_ALL);
+ else
+ _tlbiel_kernel_broadcast();
+}
+EXPORT_SYMBOL(radix__flush_tlb_kernel_range);
+
+#define TLB_FLUSH_ALL -1UL
+
+/*
+ * Number of pages above which we invalidate the entire PID rather than
+ * flush individual pages, for local and global flushes respectively.
+ *
+ * tlbie goes out to the interconnect and individual ops are more costly.
+ * It also does not iterate over sets like the local tlbiel variant when
+ * invalidating a full PID, so it has a far lower threshold to change from
+ * individual page flushes to full-pid flushes.
+ */
+static unsigned long tlb_single_page_flush_ceiling __read_mostly = 33;
+static unsigned long tlb_local_single_page_flush_ceiling __read_mostly = POWER9_TLB_SETS_RADIX * 2;
+
+static inline void __radix__flush_tlb_range(struct mm_struct *mm,
+ unsigned long start, unsigned long end)
+
+{
+ unsigned long pid;
+ unsigned int page_shift = mmu_psize_defs[mmu_virtual_psize].shift;
+ unsigned long page_size = 1UL << page_shift;
+ unsigned long nr_pages = (end - start) >> page_shift;
+ bool local, full;
+
+ pid = mm->context.id;
+ if (unlikely(pid == MMU_NO_CONTEXT))
+ return;
+
+ preempt_disable();
+ smp_mb(); /* see radix__flush_tlb_mm */
+ if (!mm_is_thread_local(mm)) {
+ if (unlikely(mm_is_singlethreaded(mm))) {
+ if (end != TLB_FLUSH_ALL) {
+ exit_flush_lazy_tlbs(mm);
+ goto is_local;
+ }
+ }
+ local = false;
+ full = (end == TLB_FLUSH_ALL ||
+ nr_pages > tlb_single_page_flush_ceiling);
+ } else {
+is_local:
+ local = true;
+ full = (end == TLB_FLUSH_ALL ||
+ nr_pages > tlb_local_single_page_flush_ceiling);
+ }
+
+ if (!mmu_has_feature(MMU_FTR_GTSE) && !local) {
+ unsigned long tgt = H_RPTI_TARGET_CMMU;
+ unsigned long pg_sizes = psize_to_rpti_pgsize(mmu_virtual_psize);
+
+ if (IS_ENABLED(CONFIG_TRANSPARENT_HUGEPAGE))
+ pg_sizes |= psize_to_rpti_pgsize(MMU_PAGE_2M);
+ if (atomic_read(&mm->context.copros) > 0)
+ tgt |= H_RPTI_TARGET_NMMU;
+ pseries_rpt_invalidate(pid, tgt, H_RPTI_TYPE_TLB, pg_sizes,
+ start, end);
+ } else if (full) {
+ if (local) {
+ _tlbiel_pid(pid, RIC_FLUSH_TLB);
+ } else {
+ if (cputlb_use_tlbie()) {
+ if (mm_needs_flush_escalation(mm))
+ _tlbie_pid(pid, RIC_FLUSH_ALL);
+ else
+ _tlbie_pid(pid, RIC_FLUSH_TLB);
+ } else {
+ _tlbiel_pid_multicast(mm, pid, RIC_FLUSH_TLB);
+ }
+ }
+ } else {
+ bool hflush;
+ unsigned long hstart, hend;
+
+ hstart = (start + PMD_SIZE - 1) & PMD_MASK;
+ hend = end & PMD_MASK;
+ hflush = IS_ENABLED(CONFIG_TRANSPARENT_HUGEPAGE) && hstart < hend;
+
+ if (local) {
+ asm volatile("ptesync": : :"memory");
+ __tlbiel_va_range(start, end, pid, page_size, mmu_virtual_psize);
+ if (hflush)
+ __tlbiel_va_range(hstart, hend, pid,
+ PMD_SIZE, MMU_PAGE_2M);
+ ppc_after_tlbiel_barrier();
+ } else if (cputlb_use_tlbie()) {
+ asm volatile("ptesync": : :"memory");
+ __tlbie_va_range(start, end, pid, page_size, mmu_virtual_psize);
+ if (hflush)
+ __tlbie_va_range(hstart, hend, pid,
+ PMD_SIZE, MMU_PAGE_2M);
+ asm volatile("eieio; tlbsync; ptesync": : :"memory");
+ } else {
+ _tlbiel_va_range_multicast(mm,
+ start, end, pid, page_size, mmu_virtual_psize, false);
+ if (hflush)
+ _tlbiel_va_range_multicast(mm,
+ hstart, hend, pid, PMD_SIZE, MMU_PAGE_2M, false);
+ }
+ }
+ preempt_enable();
+}
+
+void radix__flush_tlb_range(struct vm_area_struct *vma, unsigned long start,
+ unsigned long end)
+
+{
+#ifdef CONFIG_HUGETLB_PAGE
+ if (is_vm_hugetlb_page(vma))
+ return radix__flush_hugetlb_tlb_range(vma, start, end);
+#endif
+
+ __radix__flush_tlb_range(vma->vm_mm, start, end);
+}
+EXPORT_SYMBOL(radix__flush_tlb_range);
+
+static int radix_get_mmu_psize(int page_size)
+{
+ int psize;
+
+ if (page_size == (1UL << mmu_psize_defs[mmu_virtual_psize].shift))
+ psize = mmu_virtual_psize;
+ else if (page_size == (1UL << mmu_psize_defs[MMU_PAGE_2M].shift))
+ psize = MMU_PAGE_2M;
+ else if (page_size == (1UL << mmu_psize_defs[MMU_PAGE_1G].shift))
+ psize = MMU_PAGE_1G;
+ else
+ return -1;
+ return psize;
+}
+
+/*
+ * Flush partition scoped LPID address translation for all CPUs.
+ */
+void radix__flush_tlb_lpid_page(unsigned int lpid,
+ unsigned long addr,
+ unsigned long page_size)
+{
+ int psize = radix_get_mmu_psize(page_size);
+
+ _tlbie_lpid_va(addr, lpid, psize, RIC_FLUSH_TLB);
+}
+EXPORT_SYMBOL_GPL(radix__flush_tlb_lpid_page);
+
+/*
+ * Flush partition scoped PWC from LPID for all CPUs.
+ */
+void radix__flush_pwc_lpid(unsigned int lpid)
+{
+ _tlbie_lpid(lpid, RIC_FLUSH_PWC);
+}
+EXPORT_SYMBOL_GPL(radix__flush_pwc_lpid);
+
+/*
+ * Flush partition scoped translations from LPID (=LPIDR)
+ */
+void radix__flush_all_lpid(unsigned int lpid)
+{
+ _tlbie_lpid(lpid, RIC_FLUSH_ALL);
+}
+EXPORT_SYMBOL_GPL(radix__flush_all_lpid);
+
+/*
+ * Flush process scoped translations from LPID (=LPIDR)
+ */
+void radix__flush_all_lpid_guest(unsigned int lpid)
+{
+ _tlbie_lpid_guest(lpid, RIC_FLUSH_ALL);
+}
+
+static void radix__flush_tlb_pwc_range_psize(struct mm_struct *mm, unsigned long start,
+ unsigned long end, int psize);
+
+void radix__tlb_flush(struct mmu_gather *tlb)
+{
+ int psize = 0;
+ struct mm_struct *mm = tlb->mm;
+ int page_size = tlb->page_size;
+ unsigned long start = tlb->start;
+ unsigned long end = tlb->end;
+
+ /*
+ * if page size is not something we understand, do a full mm flush
+ *
+ * A "fullmm" flush must always do a flush_all_mm (RIC=2) flush
+ * that flushes the process table entry cache upon process teardown.
+ * See the comment for radix in arch_exit_mmap().
+ */
+ if (tlb->fullmm || tlb->need_flush_all) {
+ __flush_all_mm(mm, true);
+ } else if ( (psize = radix_get_mmu_psize(page_size)) == -1) {
+ if (!tlb->freed_tables)
+ radix__flush_tlb_mm(mm);
+ else
+ radix__flush_all_mm(mm);
+ } else {
+ if (!tlb->freed_tables)
+ radix__flush_tlb_range_psize(mm, start, end, psize);
+ else
+ radix__flush_tlb_pwc_range_psize(mm, start, end, psize);
+ }
+}
+
+static void __radix__flush_tlb_range_psize(struct mm_struct *mm,
+ unsigned long start, unsigned long end,
+ int psize, bool also_pwc)
+{
+ unsigned long pid;
+ unsigned int page_shift = mmu_psize_defs[psize].shift;
+ unsigned long page_size = 1UL << page_shift;
+ unsigned long nr_pages = (end - start) >> page_shift;
+ bool local, full;
+
+ pid = mm->context.id;
+ if (unlikely(pid == MMU_NO_CONTEXT))
+ return;
+
+ preempt_disable();
+ smp_mb(); /* see radix__flush_tlb_mm */
+ if (!mm_is_thread_local(mm)) {
+ if (unlikely(mm_is_singlethreaded(mm))) {
+ if (end != TLB_FLUSH_ALL) {
+ exit_flush_lazy_tlbs(mm);
+ goto is_local;
+ }
+ }
+ local = false;
+ full = (end == TLB_FLUSH_ALL ||
+ nr_pages > tlb_single_page_flush_ceiling);
+ } else {
+is_local:
+ local = true;
+ full = (end == TLB_FLUSH_ALL ||
+ nr_pages > tlb_local_single_page_flush_ceiling);
+ }
+
+ if (!mmu_has_feature(MMU_FTR_GTSE) && !local) {
+ unsigned long tgt = H_RPTI_TARGET_CMMU;
+ unsigned long type = H_RPTI_TYPE_TLB;
+ unsigned long pg_sizes = psize_to_rpti_pgsize(psize);
+
+ if (also_pwc)
+ type |= H_RPTI_TYPE_PWC;
+ if (atomic_read(&mm->context.copros) > 0)
+ tgt |= H_RPTI_TARGET_NMMU;
+ pseries_rpt_invalidate(pid, tgt, type, pg_sizes, start, end);
+ } else if (full) {
+ if (local) {
+ _tlbiel_pid(pid, also_pwc ? RIC_FLUSH_ALL : RIC_FLUSH_TLB);
+ } else {
+ if (cputlb_use_tlbie()) {
+ if (mm_needs_flush_escalation(mm))
+ also_pwc = true;
+
+ _tlbie_pid(pid,
+ also_pwc ? RIC_FLUSH_ALL : RIC_FLUSH_TLB);
+ } else {
+ _tlbiel_pid_multicast(mm, pid,
+ also_pwc ? RIC_FLUSH_ALL : RIC_FLUSH_TLB);
+ }
+
+ }
+ } else {
+ if (local)
+ _tlbiel_va_range(start, end, pid, page_size, psize, also_pwc);
+ else if (cputlb_use_tlbie())
+ _tlbie_va_range(start, end, pid, page_size, psize, also_pwc);
+ else
+ _tlbiel_va_range_multicast(mm,
+ start, end, pid, page_size, psize, also_pwc);
+ }
+ preempt_enable();
+}
+
+void radix__flush_tlb_range_psize(struct mm_struct *mm, unsigned long start,
+ unsigned long end, int psize)
+{
+ return __radix__flush_tlb_range_psize(mm, start, end, psize, false);
+}
+
+static void radix__flush_tlb_pwc_range_psize(struct mm_struct *mm, unsigned long start,
+ unsigned long end, int psize)
+{
+ __radix__flush_tlb_range_psize(mm, start, end, psize, true);
+}
+
+#ifdef CONFIG_TRANSPARENT_HUGEPAGE
+void radix__flush_tlb_collapsed_pmd(struct mm_struct *mm, unsigned long addr)
+{
+ unsigned long pid, end;
+
+ pid = mm->context.id;
+ if (unlikely(pid == MMU_NO_CONTEXT))
+ return;
+
+ /* 4k page size, just blow the world */
+ if (PAGE_SIZE == 0x1000) {
+ radix__flush_all_mm(mm);
+ return;
+ }
+
+ end = addr + HPAGE_PMD_SIZE;
+
+ /* Otherwise first do the PWC, then iterate the pages. */
+ preempt_disable();
+ smp_mb(); /* see radix__flush_tlb_mm */
+ if (!mm_is_thread_local(mm)) {
+ if (unlikely(mm_is_singlethreaded(mm))) {
+ exit_flush_lazy_tlbs(mm);
+ goto local;
+ }
+ if (!mmu_has_feature(MMU_FTR_GTSE)) {
+ unsigned long tgt, type, pg_sizes;
+
+ tgt = H_RPTI_TARGET_CMMU;
+ type = H_RPTI_TYPE_TLB | H_RPTI_TYPE_PWC |
+ H_RPTI_TYPE_PRT;
+ pg_sizes = psize_to_rpti_pgsize(mmu_virtual_psize);
+
+ if (atomic_read(&mm->context.copros) > 0)
+ tgt |= H_RPTI_TARGET_NMMU;
+ pseries_rpt_invalidate(pid, tgt, type, pg_sizes,
+ addr, end);
+ } else if (cputlb_use_tlbie())
+ _tlbie_va_range(addr, end, pid, PAGE_SIZE, mmu_virtual_psize, true);
+ else
+ _tlbiel_va_range_multicast(mm,
+ addr, end, pid, PAGE_SIZE, mmu_virtual_psize, true);
+ } else {
+local:
+ _tlbiel_va_range(addr, end, pid, PAGE_SIZE, mmu_virtual_psize, true);
+ }
+
+ preempt_enable();
+}
+#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
+
+void radix__flush_pmd_tlb_range(struct vm_area_struct *vma,
+ unsigned long start, unsigned long end)
+{
+ radix__flush_tlb_range_psize(vma->vm_mm, start, end, MMU_PAGE_2M);
+}
+EXPORT_SYMBOL(radix__flush_pmd_tlb_range);
+
+void radix__flush_tlb_all(void)
+{
+ unsigned long rb,prs,r,rs;
+ unsigned long ric = RIC_FLUSH_ALL;
+
+ rb = 0x3 << PPC_BITLSHIFT(53); /* IS = 3 */
+ prs = 0; /* partition scoped */
+ r = 1; /* radix format */
+ rs = 1 & ((1UL << 32) - 1); /* any LPID value to flush guest mappings */
+
+ asm volatile("ptesync": : :"memory");
+ /*
+ * now flush guest entries by passing PRS = 1 and LPID != 0
+ */
+ asm volatile(PPC_TLBIE_5(%0, %4, %3, %2, %1)
+ : : "r"(rb), "i"(r), "i"(1), "i"(ric), "r"(rs) : "memory");
+ /*
+ * now flush host entires by passing PRS = 0 and LPID == 0
+ */
+ asm volatile(PPC_TLBIE_5(%0, %4, %3, %2, %1)
+ : : "r"(rb), "i"(r), "i"(prs), "i"(ric), "r"(0) : "memory");
+ asm volatile("eieio; tlbsync; ptesync": : :"memory");
+}
+
+#ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE
+extern void radix_kvm_prefetch_workaround(struct mm_struct *mm)
+{
+ unsigned long pid = mm->context.id;
+
+ if (unlikely(pid == MMU_NO_CONTEXT))
+ return;
+
+ if (!cpu_has_feature(CPU_FTR_P9_RADIX_PREFETCH_BUG))
+ return;
+
+ /*
+ * If this context hasn't run on that CPU before and KVM is
+ * around, there's a slim chance that the guest on another
+ * CPU just brought in obsolete translation into the TLB of
+ * this CPU due to a bad prefetch using the guest PID on
+ * the way into the hypervisor.
+ *
+ * We work around this here. If KVM is possible, we check if
+ * any sibling thread is in KVM. If it is, the window may exist
+ * and thus we flush that PID from the core.
+ *
+ * A potential future improvement would be to mark which PIDs
+ * have never been used on the system and avoid it if the PID
+ * is new and the process has no other cpumask bit set.
+ */
+ if (cpu_has_feature(CPU_FTR_HVMODE) && radix_enabled()) {
+ int cpu = smp_processor_id();
+ int sib = cpu_first_thread_sibling(cpu);
+ bool flush = false;
+
+ for (; sib <= cpu_last_thread_sibling(cpu) && !flush; sib++) {
+ if (sib == cpu)
+ continue;
+ if (!cpu_possible(sib))
+ continue;
+ if (paca_ptrs[sib]->kvm_hstate.kvm_vcpu)
+ flush = true;
+ }
+ if (flush)
+ _tlbiel_pid(pid, RIC_FLUSH_ALL);
+ }
+}
+EXPORT_SYMBOL_GPL(radix_kvm_prefetch_workaround);
+#endif /* CONFIG_KVM_BOOK3S_HV_POSSIBLE */