[PATCH v6 12/28] KVM: s390: KVM-specific bitfields and helper functions

Claudio Imbrenda
2025-12-22T16:51:07Z

Add KVM-s390 specific bitfields and helper functions to manipulate DAT
tables.

Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
---
arch/s390/kvm/dat.h | 720 ++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 720 insertions(+)
create mode 100644 arch/s390/kvm/dat.h

diff --git a/arch/s390/kvm/dat.h b/arch/s390/kvm/dat.h
new file mode 100644
index 000000000000..4d2b7a7bf898
--- /dev/null
+++ b/arch/s390/kvm/dat.h
@@ -0,0 +1,720 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * KVM guest address space mapping code
+ *
+ * Copyright IBM Corp. 2024, 2025
+ * Author(s): Claudio Imbrenda <imbrenda@linux.ibm.com>
+ */
+
+#ifndef __KVM_S390_DAT_H
+#define __KVM_S390_DAT_H
+
+#include <linux/radix-tree.h>
+#include <linux/refcount.h>
+#include <linux/io.h>
+#include <linux/kvm_types.h>
+#include <linux/pgalloc.h>
+#include <asm/tlbflush.h>
+#include <asm/dat-bits.h>
+
+#define _ASCE(x) ((union asce) { .val = (x), })
+#define NULL_ASCE _ASCE(0)
+
+enum {
+ _DAT_TOKEN_NONE = 0,
+ _DAT_TOKEN_PIC,
+};
+
+#define _CRSTE_TOK(l, t, p) ((union crste) { \
+ .tok.i = 1, \
+ .tok.tt = (l), \
+ .tok.type = (t), \
+ .tok.par = (p) \
+ })
+#define _CRSTE_PIC(l, p) _CRSTE_TOK(l, _DAT_TOKEN_PIC, p)
+
+#define _CRSTE_HOLE(l) _CRSTE_PIC(l, PGM_ADDRESSING)
+#define _CRSTE_EMPTY(l) _CRSTE_TOK(l, _DAT_TOKEN_NONE, 0)
+
+#define _PMD_EMPTY _CRSTE_EMPTY(TABLE_TYPE_SEGMENT)
+
+#define _PTE_TOK(t, p) ((union pte) { .tok.i = 1, .tok.type = (t), .tok.par = (p) })
+#define _PTE_EMPTY _PTE_TOK(_DAT_TOKEN_NONE, 0)
+
+/* This fake table type is used for page table walks (both for normal page tables and vSIE) */
+#define TABLE_TYPE_PAGE_TABLE -1
+
+enum dat_walk_flags {
+ DAT_WALK_CONTINUE = 0x20,
+ DAT_WALK_IGN_HOLES = 0x10,
+ DAT_WALK_SPLIT = 0x08,
+ DAT_WALK_ALLOC = 0x04,
+ DAT_WALK_ANY = 0x02,
+ DAT_WALK_LEAF = 0x01,
+ DAT_WALK_DEFAULT = 0
+};
+
+#define DAT_WALK_SPLIT_ALLOC (DAT_WALK_SPLIT | DAT_WALK_ALLOC)
+#define DAT_WALK_ALLOC_CONTINUE (DAT_WALK_CONTINUE | DAT_WALK_ALLOC)
+#define DAT_WALK_LEAF_ALLOC (DAT_WALK_LEAF | DAT_WALK_ALLOC)
+
+union pte {
+ unsigned long val;
+ union page_table_entry h;
+ struct {
+ unsigned long :56; /* Hardware bits */
+ unsigned long u : 1; /* Page unused */
+ unsigned long s : 1; /* Special */
+ unsigned long w : 1; /* Writable */
+ unsigned long r : 1; /* Readable */
+ unsigned long d : 1; /* Dirty */
+ unsigned long y : 1; /* Young */
+ unsigned long sd: 1; /* Soft dirty */
+ unsigned long pr: 1; /* Present */
+ } s;
+ struct {
+ unsigned char hwbytes[7];
+ unsigned char swbyte;
+ };
+ union {
+ struct {
+ unsigned long type :16; /* Token type */
+ unsigned long par :16; /* Token parameter */
+ unsigned long :20;
+ unsigned long : 1; /* Must be 0 */
+ unsigned long i : 1; /* Must be 1 */
+ unsigned long : 2;
+ unsigned long : 7;
+ unsigned long pr : 1; /* Must be 0 */
+ };
+ struct {
+ unsigned long token:32; /* Token and parameter */
+ unsigned long :32;
+ };
+ } tok;
+};
+
+/* Soft dirty, needed as macro for atomic operations on ptes */
+#define _PAGE_SD 0x002
+
+/* Needed as macro to perform atomic operations */
+#define PGSTE_CMMA_D_BIT 0x0000000000008000UL /* CMMA dirty soft-bit */
+
+enum pgste_gps_usage {
+ PGSTE_GPS_USAGE_STABLE = 0,
+ PGSTE_GPS_USAGE_UNUSED,
+ PGSTE_GPS_USAGE_POT_VOLATILE,
+ PGSTE_GPS_USAGE_VOLATILE,
+};
+
+union pgste {
+ unsigned long val;
+ struct {
+ unsigned long acc : 4;
+ unsigned long fp : 1;
+ unsigned long : 3;
+ unsigned long pcl : 1;
+ unsigned long hr : 1;
+ unsigned long hc : 1;
+ unsigned long : 2;
+ unsigned long gr : 1;
+ unsigned long gc : 1;
+ unsigned long : 1;
+ unsigned long :16; /* val16 */
+ unsigned long zero : 1;
+ unsigned long nodat : 1;
+ unsigned long : 4;
+ unsigned long usage : 2;
+ unsigned long : 8;
+ unsigned long cmma_d : 1; /* Dirty flag for CMMA bits */
+ unsigned long prefix_notif : 1; /* Guest prefix invalidation notification */
+ unsigned long vsie_notif : 1; /* Referenced in a shadow table */
+ unsigned long : 5;
+ unsigned long : 8;
+ };
+ struct {
+ unsigned short hwbytes0;
+ unsigned short val16; /* used to store chunked values, see dat_{s,g}et_ptval() */
+ unsigned short hwbytes4;
+ unsigned char flags; /* maps to the software bits */
+ unsigned char hwbyte7;
+ } __packed;
+};
+
+union pmd {
+ unsigned long val;
+ union segment_table_entry h;
+ struct {
+ struct {
+ unsigned long :44; /* HW */
+ unsigned long : 3; /* Unused */
+ unsigned long : 1; /* HW */
+ unsigned long w : 1; /* Writable soft-bit */
+ unsigned long r : 1; /* Readable soft-bit */
+ unsigned long d : 1; /* Dirty */
+ unsigned long y : 1; /* Young */
+ unsigned long prefix_notif : 1; /* Guest prefix invalidation notification */
+ unsigned long : 3; /* HW */
+ unsigned long vsie_notif : 1; /* Referenced in a shadow table */
+ unsigned long : 1; /* Unused */
+ unsigned long : 4; /* HW */
+ unsigned long sd : 1; /* Soft-Dirty */
+ unsigned long pr : 1; /* Present */
+ } fc1;
+ } s;
+};
+
+union pud {
+ unsigned long val;
+ union region3_table_entry h;
+ struct {
+ struct {
+ unsigned long :33; /* HW */
+ unsigned long :14; /* Unused */
+ unsigned long : 1; /* HW */
+ unsigned long w : 1; /* Writable soft-bit */
+ unsigned long r : 1; /* Readable soft-bit */
+ unsigned long d : 1; /* Dirty */
+ unsigned long y : 1; /* Young */
+ unsigned long prefix_notif : 1; /* Guest prefix invalidation notification */
+ unsigned long : 3; /* HW */
+ unsigned long vsie_notif : 1; /* Referenced in a shadow table */
+ unsigned long : 1; /* Unused */
+ unsigned long : 4; /* HW */
+ unsigned long sd : 1; /* Soft-Dirty */
+ unsigned long pr : 1; /* Present */
+ } fc1;
+ } s;
+};
+
+union p4d {
+ unsigned long val;
+ union region2_table_entry h;
+};
+
+union pgd {
+ unsigned long val;
+ union region1_table_entry h;
+};
+
+union crste {
+ unsigned long val;
+ union {
+ struct {
+ unsigned long :52;
+ unsigned long : 1;
+ unsigned long fc: 1;
+ unsigned long p : 1;
+ unsigned long : 1;
+ unsigned long : 2;
+ unsigned long i : 1;
+ unsigned long : 1;
+ unsigned long tt: 2;
+ unsigned long : 2;
+ };
+ struct {
+ unsigned long to:52;
+ unsigned long : 1;
+ unsigned long fc: 1;
+ unsigned long p : 1;
+ unsigned long : 1;
+ unsigned long tf: 2;
+ unsigned long i : 1;
+ unsigned long : 1;
+ unsigned long tt: 2;
+ unsigned long tl: 2;
+ } fc0;
+ struct {
+ unsigned long :47;
+ unsigned long av : 1; /* ACCF-Validity Control */
+ unsigned long acc: 4; /* Access-Control Bits */
+ unsigned long f : 1; /* Fetch-Protection Bit */
+ unsigned long fc : 1; /* Format-Control */
+ unsigned long p : 1; /* DAT-Protection Bit */
+ unsigned long iep: 1; /* Instruction-Execution-Protection */
+ unsigned long : 2;
+ unsigned long i : 1; /* Segment-Invalid Bit */
+ unsigned long cs : 1; /* Common-Segment Bit */
+ unsigned long tt : 2; /* Table-Type Bits */
+ unsigned long : 2;
+ } fc1;
+ } h;
+ struct {
+ struct {
+ unsigned long :47;
+ unsigned long : 1; /* HW (should be 0) */
+ unsigned long w : 1; /* Writable */
+ unsigned long r : 1; /* Readable */
+ unsigned long d : 1; /* Dirty */
+ unsigned long y : 1; /* Young */
+ unsigned long prefix_notif : 1; /* Guest prefix invalidation notification */
+ unsigned long : 3; /* HW */
+ unsigned long vsie_notif : 1; /* Referenced in a shadow table */
+ unsigned long : 1;
+ unsigned long : 4; /* HW */
+ unsigned long sd : 1; /* Soft-Dirty */
+ unsigned long pr : 1; /* Present */
+ } fc1;
+ } s;
+ union {
+ struct {
+ unsigned long type :16; /* Token type */
+ unsigned long par :16; /* Token parameter */
+ unsigned long :26;
+ unsigned long i : 1; /* Must be 1 */
+ unsigned long : 1;
+ unsigned long tt : 2;
+ unsigned long : 1;
+ unsigned long pr : 1; /* Must be 0 */
+ };
+ struct {
+ unsigned long token:32; /* Token and parameter */
+ unsigned long :32;
+ };
+ } tok;
+ union pmd pmd;
+ union pud pud;
+ union p4d p4d;
+ union pgd pgd;
+};
+
+union skey {
+ unsigned char skey;
+ struct {
+ unsigned char acc :4;
+ unsigned char fp :1;
+ unsigned char r :1;
+ unsigned char c :1;
+ unsigned char zero:1;
+ };
+};
+
+static_assert(sizeof(union pgste) == sizeof(unsigned long));
+static_assert(sizeof(union pte) == sizeof(unsigned long));
+static_assert(sizeof(union pmd) == sizeof(unsigned long));
+static_assert(sizeof(union pud) == sizeof(unsigned long));
+static_assert(sizeof(union p4d) == sizeof(unsigned long));
+static_assert(sizeof(union pgd) == sizeof(unsigned long));
+static_assert(sizeof(union crste) == sizeof(unsigned long));
+static_assert(sizeof(union skey) == sizeof(char));
+
+struct segment_table {
+ union pmd pmds[_CRST_ENTRIES];
+};
+
+struct region3_table {
+ union pud puds[_CRST_ENTRIES];
+};
+
+struct region2_table {
+ union p4d p4ds[_CRST_ENTRIES];
+};
+
+struct region1_table {
+ union pgd pgds[_CRST_ENTRIES];
+};
+
+struct crst_table {
+ union {
+ union crste crstes[_CRST_ENTRIES];
+ struct segment_table segment;
+ struct region3_table region3;
+ struct region2_table region2;
+ struct region1_table region1;
+ };
+};
+
+struct page_table {
+ union pte ptes[_PAGE_ENTRIES];
+ union pgste pgstes[_PAGE_ENTRIES];
+};
+
+static_assert(sizeof(struct crst_table) == _CRST_TABLE_SIZE);
+static_assert(sizeof(struct page_table) == PAGE_SIZE);
+
+/**
+ * _pte() - Useful constructor for union pte
+ * @pfn: the pfn this pte should point to.
+ * @writable: whether the pte should be writable.
+ * @dirty: whether the pte should be dirty.
+ * @special: whether the pte should be marked as special
+ *
+ * The pte is also marked as young and present. If the pte is marked as dirty,
+ * it gets marked as soft-dirty too. If the pte is not dirty, the hardware
+ * protect bit is set (independently of the write softbit); this way proper
+ * dirty tracking can be performed.
+ *
+ * Return: a union pte value.
+ */
+static inline union pte _pte(kvm_pfn_t pfn, bool writable, bool dirty, bool special)
+{
+ union pte res = { .val = PFN_PHYS(pfn) };
+
+ res.h.p = !dirty;
+ res.s.y = 1;
+ res.s.pr = 1;
+ res.s.w = writable;
+ res.s.d = dirty;
+ res.s.sd = dirty;
+ res.s.s = special;
+ return res;
+}
+
+static inline union crste _crste_fc0(kvm_pfn_t pfn, int tt)
+{
+ union crste res = { .val = PFN_PHYS(pfn) };
+
+ res.h.tt = tt;
+ res.h.fc0.tl = _REGION_ENTRY_LENGTH;
+ res.h.fc0.tf = 0;
+ return res;
+}
+
+/**
+ * _crste() - Useful constructor for union crste with FC=1
+ * @pfn: the pfn this pte should point to.
+ * @tt: the table type
+ * @writable: whether the pte should be writable.
+ * @dirty: whether the pte should be dirty.
+ *
+ * The crste is also marked as young and present. If the crste is marked as
+ * dirty, it gets marked as soft-dirty too. If the crste is not dirty, the
+ * hardware protect bit is set (independently of the write softbit); this way
+ * proper dirty tracking can be performed.
+ *
+ * Return: a union crste value.
+ */
+static inline union crste _crste_fc1(kvm_pfn_t pfn, int tt, bool writable, bool dirty)
+{
+ union crste res = { .val = PFN_PHYS(pfn) & _SEGMENT_MASK };
+
+ res.h.tt = tt;
+ res.h.p = !dirty;
+ res.h.fc = 1;
+ res.s.fc1.y = 1;
+ res.s.fc1.pr = 1;
+ res.s.fc1.w = writable;
+ res.s.fc1.d = dirty;
+ res.s.fc1.sd = dirty;
+ return res;
+}
+
+/**
+ * struct vsie_rmap - reverse mapping for shadow page table entries
+ * @next: pointer to next rmap in the list
+ * @r_gfn: virtual rmap address in the shadow guest address space
+ */
+struct vsie_rmap {
+ struct vsie_rmap *next;
+ union {
+ unsigned long val;
+ struct {
+ long level: 8;
+ unsigned long : 4;
+ unsigned long r_gfn:52;
+ };
+ };
+};
+
+static_assert(sizeof(struct vsie_rmap) == 2 * sizeof(long));
+
+static inline struct crst_table *crste_table_start(union crste *crstep)
+{
+ return (struct crst_table *)ALIGN_DOWN((unsigned long)crstep, _CRST_TABLE_SIZE);
+}
+
+static inline struct page_table *pte_table_start(union pte *ptep)
+{
+ return (struct page_table *)ALIGN_DOWN((unsigned long)ptep, _PAGE_TABLE_SIZE);
+}
+
+static inline bool crdte_crste(union crste *crstep, union crste old, union crste new, gfn_t gfn,
+ union asce asce)
+{
+ unsigned long dtt = 0x10 | new.h.tt << 2;
+ void *table = crste_table_start(crstep);
+
+ return crdte(old.val, new.val, table, dtt, gfn_to_gpa(gfn), asce.val);
+}
+
+/**
+ * idte_crste() - invalidate a crste entry using idte
+ * @crstep: pointer to the crste to be invalidated
+ * @gfn: a gfn mapped by the crste
+ * @opt: options for the idte instruction
+ * @asce: the asce
+ * @local: whether the operation is cpu-local
+ */
+static __always_inline void idte_crste(union crste *crstep, gfn_t gfn, unsigned long opt,
+ union asce asce, int local)
+{
+ unsigned long table_origin = __pa(crste_table_start(crstep));
+ unsigned long gaddr = gfn_to_gpa(gfn) & HPAGE_MASK;
+
+ if (__builtin_constant_p(opt) && opt == 0) {
+ /* flush without guest asce */
+ asm volatile("idte %[table_origin],0,%[gaddr],%[local]"
+ : "+m" (*crstep)
+ : [table_origin] "a" (table_origin), [gaddr] "a" (gaddr),
+ [local] "i" (local)
+ : "cc");
+ } else {
+ /* flush with guest asce */
+ asm volatile("idte %[table_origin],%[asce],%[gaddr_opt],%[local]"
+ : "+m" (*crstep)
+ : [table_origin] "a" (table_origin), [gaddr_opt] "a" (gaddr | opt),
+ [asce] "a" (asce.val), [local] "i" (local)
+ : "cc");
+ }
+}
+
+static inline void dat_init_pgstes(struct page_table *pt, unsigned long val)
+{
+ memset64((void *)pt->pgstes, val, PTRS_PER_PTE);
+}
+
+static inline void dat_init_page_table(struct page_table *pt, unsigned long ptes,
+ unsigned long pgstes)
+{
+ memset64((void *)pt->ptes, ptes, PTRS_PER_PTE);
+ dat_init_pgstes(pt, pgstes);
+}
+
+static inline gfn_t asce_end(union asce asce)
+{
+ return 1ULL << ((asce.dt + 1) * 11 + _SEGMENT_SHIFT - PAGE_SHIFT);
+}
+
+#define _CRSTE(x) ((union crste) { .val = _Generic((x), \
+ union pgd : (x).val, \
+ union p4d : (x).val, \
+ union pud : (x).val, \
+ union pmd : (x).val, \
+ union crste : (x).val)})
+
+#define _CRSTEP(x) ((union crste *)_Generic((*(x)), \
+ union pgd : (x), \
+ union p4d : (x), \
+ union pud : (x), \
+ union pmd : (x), \
+ union crste : (x)))
+
+#define _CRSTP(x) ((struct crst_table *)_Generic((*(x)), \
+ struct crst_table : (x), \
+ struct segment_table : (x), \
+ struct region3_table : (x), \
+ struct region2_table : (x), \
+ struct region1_table : (x)))
+
+static inline bool asce_contains_gfn(union asce asce, gfn_t gfn)
+{
+ return gfn < asce_end(asce);
+}
+
+static inline bool is_pmd(union crste crste)
+{
+ return crste.h.tt == TABLE_TYPE_SEGMENT;
+}
+
+static inline bool is_pud(union crste crste)
+{
+ return crste.h.tt == TABLE_TYPE_REGION3;
+}
+
+static inline bool is_p4d(union crste crste)
+{
+ return crste.h.tt == TABLE_TYPE_REGION2;
+}
+
+static inline bool is_pgd(union crste crste)
+{
+ return crste.h.tt == TABLE_TYPE_REGION1;
+}
+
+static inline phys_addr_t pmd_origin_large(union pmd pmd)
+{
+ return pmd.val & _SEGMENT_ENTRY_ORIGIN_LARGE;
+}
+
+static inline phys_addr_t pud_origin_large(union pud pud)
+{
+ return pud.val & _REGION3_ENTRY_ORIGIN_LARGE;
+}
+
+/**
+ * crste_origin_large() - Return the large frame origin of a large crste
+ * @crste: The crste whose origin is to be returned. Should be either a
+ * region-3 table entry or a segment table entry, in both cases with
+ * FC set to 1 (large pages).
+ *
+ * Return: The origin of the large frame pointed to by @crste, or -1 if the
+ * crste was not large (wrong table type, or FC==0)
+ */
+static inline phys_addr_t crste_origin_large(union crste crste)
+{
+ if (unlikely(!crste.h.fc || crste.h.tt > TABLE_TYPE_REGION3))
+ return -1;
+ if (is_pmd(crste))
+ return pmd_origin_large(crste.pmd);
+ return pud_origin_large(crste.pud);
+}
+
+#define crste_origin(x) (_Generic((x), \
+ union pmd : (x).val & _SEGMENT_ENTRY_ORIGIN, \
+ union pud : (x).val & _REGION_ENTRY_ORIGIN, \
+ union p4d : (x).val & _REGION_ENTRY_ORIGIN, \
+ union pgd : (x).val & _REGION_ENTRY_ORIGIN))
+
+static inline unsigned long pte_origin(union pte pte)
+{
+ return pte.val & PAGE_MASK;
+}
+
+static inline bool pmd_prefix(union pmd pmd)
+{
+ return pmd.h.fc && pmd.s.fc1.prefix_notif;
+}
+
+static inline bool pud_prefix(union pud pud)
+{
+ return pud.h.fc && pud.s.fc1.prefix_notif;
+}
+
+static inline bool crste_leaf(union crste crste)
+{
+ return (crste.h.tt <= TABLE_TYPE_REGION3) && crste.h.fc;
+}
+
+static inline bool crste_prefix(union crste crste)
+{
+ return crste_leaf(crste) && crste.s.fc1.prefix_notif;
+}
+
+static inline bool crste_dirty(union crste crste)
+{
+ return crste_leaf(crste) && crste.s.fc1.d;
+}
+
+static inline union pgste *pgste_of(union pte *pte)
+{
+ return (union pgste *)(pte + _PAGE_ENTRIES);
+}
+
+static inline bool pte_hole(union pte pte)
+{
+ return pte.h.i && !pte.tok.pr && pte.tok.type != _DAT_TOKEN_NONE;
+}
+
+static inline bool _crste_hole(union crste crste)
+{
+ return crste.h.i && !crste.tok.pr && crste.tok.type != _DAT_TOKEN_NONE;
+}
+
+#define crste_hole(x) _crste_hole(_CRSTE(x))
+
+static inline bool _crste_none(union crste crste)
+{
+ return crste.h.i && !crste.tok.pr && crste.tok.type == _DAT_TOKEN_NONE;
+}
+
+#define crste_none(x) _crste_none(_CRSTE(x))
+
+static inline phys_addr_t large_pud_to_phys(union pud pud, gfn_t gfn)
+{
+ return pud_origin_large(pud) | (gfn_to_gpa(gfn) & ~_REGION3_MASK);
+}
+
+static inline phys_addr_t large_pmd_to_phys(union pmd pmd, gfn_t gfn)
+{
+ return pmd_origin_large(pmd) | (gfn_to_gpa(gfn) & ~_SEGMENT_MASK);
+}
+
+static inline phys_addr_t large_crste_to_phys(union crste crste, gfn_t gfn)
+{
+ if (unlikely(!crste.h.fc || crste.h.tt > TABLE_TYPE_REGION3))
+ return -1;
+ if (is_pmd(crste))
+ return large_pmd_to_phys(crste.pmd, gfn);
+ return large_pud_to_phys(crste.pud, gfn);
+}
+
+static inline bool cspg_crste(union crste *crstep, union crste old, union crste new)
+{
+ return cspg(&crstep->val, old.val, new.val);
+}
+
+static inline struct page_table *dereference_pmd(union pmd pmd)
+{
+ return phys_to_virt(crste_origin(pmd));
+}
+
+static inline struct segment_table *dereference_pud(union pud pud)
+{
+ return phys_to_virt(crste_origin(pud));
+}
+
+static inline struct region3_table *dereference_p4d(union p4d p4d)
+{
+ return phys_to_virt(crste_origin(p4d));
+}
+
+static inline struct region2_table *dereference_pgd(union pgd pgd)
+{
+ return phys_to_virt(crste_origin(pgd));
+}
+
+static inline struct crst_table *_dereference_crste(union crste crste)
+{
+ if (unlikely(is_pmd(crste)))
+ return NULL;
+ return phys_to_virt(crste_origin(crste.pud));
+}
+
+#define dereference_crste(x) (_Generic((x), \
+ union pud : _dereference_crste(_CRSTE(x)), \
+ union p4d : _dereference_crste(_CRSTE(x)), \
+ union pgd : _dereference_crste(_CRSTE(x)), \
+ union crste : _dereference_crste(_CRSTE(x))))
+
+static inline struct crst_table *dereference_asce(union asce asce)
+{
+ return phys_to_virt(asce.val & _ASCE_ORIGIN);
+}
+
+static inline void asce_flush_tlb(union asce asce)
+{
+ __tlb_flush_idte(asce.val);
+}
+
+static inline bool pgste_get_trylock(union pte *ptep, union pgste *res)
+{
+ union pgste *pgstep = pgste_of(ptep);
+ union pgste old_pgste;
+
+ if (READ_ONCE(pgstep->val) & PGSTE_PCL_BIT)
+ return false;
+ old_pgste.val = __atomic64_or_barrier(PGSTE_PCL_BIT, &pgstep->val);
+ if (old_pgste.pcl)
+ return false;
+ old_pgste.pcl = 1;
+ *res = old_pgste;
+ return true;
+}
+
+static inline union pgste pgste_get_lock(union pte *ptep)
+{
+ union pgste res;
+
+ while (!pgste_get_trylock(ptep, &res))
+ cpu_relax();
+ return res;
+}
+
+static inline void pgste_set_unlock(union pte *ptep, union pgste pgste)
+{
+ pgste.pcl = 0;
+ barrier();
+ WRITE_ONCE(*pgste_of(ptep), pgste);
+}
+
+#endif /* __KVM_S390_DAT_H */
--
2.52.0