xref: /linux/arch/s390/kvm/dat.h (revision 6b802031877a995456c528095c41d1948546bf45)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  *  KVM guest address space mapping code
4  *
5  *    Copyright IBM Corp. 2024, 2025
6  *    Author(s): Claudio Imbrenda <imbrenda@linux.ibm.com>
7  */
8 
9 #ifndef __KVM_S390_DAT_H
10 #define __KVM_S390_DAT_H
11 
12 #include <linux/radix-tree.h>
13 #include <linux/refcount.h>
14 #include <linux/io.h>
15 #include <linux/kvm_types.h>
16 #include <linux/pgalloc.h>
17 #include <asm/tlbflush.h>
18 #include <asm/dat-bits.h>
19 
20 /*
21  * Base address and length must be sent at the start of each block, therefore
22  * it's cheaper to send some clean data, as long as it's less than the size of
23  * two longs.
24  */
25 #define KVM_S390_MAX_BIT_DISTANCE (2 * sizeof(void *))
26 /* For consistency */
27 #define KVM_S390_CMMA_SIZE_MAX ((u32)KVM_S390_SKEYS_MAX)
28 
29 #define _ASCE(x) ((union asce) { .val = (x), })
30 #define NULL_ASCE _ASCE(0)
31 
32 enum {
33 	_DAT_TOKEN_NONE = 0,
34 	_DAT_TOKEN_PIC,
35 };
36 
37 #define _CRSTE_TOK(l, t, p) ((union crste) {	\
38 		.tok.i = 1,			\
39 		.tok.tt = (l),			\
40 		.tok.type = (t),		\
41 		.tok.par = (p)			\
42 	})
43 #define _CRSTE_PIC(l, p) _CRSTE_TOK(l, _DAT_TOKEN_PIC, p)
44 
45 #define _CRSTE_HOLE(l) _CRSTE_PIC(l, PGM_ADDRESSING)
46 #define _CRSTE_EMPTY(l) _CRSTE_TOK(l, _DAT_TOKEN_NONE, 0)
47 
48 #define _PMD_EMPTY _CRSTE_EMPTY(TABLE_TYPE_SEGMENT)
49 
50 #define _PTE_TOK(t, p) ((union pte) { .tok.i = 1, .tok.type = (t), .tok.par = (p) })
51 #define _PTE_EMPTY _PTE_TOK(_DAT_TOKEN_NONE, 0)
52 
53 /* This fake table type is used for page table walks (both for normal page tables and vSIE) */
54 #define TABLE_TYPE_PAGE_TABLE -1
55 
56 enum dat_walk_flags {
57 	DAT_WALK_USES_SKEYS	= 0x40,
58 	DAT_WALK_CONTINUE	= 0x20,
59 	DAT_WALK_IGN_HOLES	= 0x10,
60 	DAT_WALK_SPLIT		= 0x08,
61 	DAT_WALK_ALLOC		= 0x04,
62 	DAT_WALK_ANY		= 0x02,
63 	DAT_WALK_LEAF		= 0x01,
64 	DAT_WALK_DEFAULT	= 0
65 };
66 
67 #define DAT_WALK_SPLIT_ALLOC (DAT_WALK_SPLIT | DAT_WALK_ALLOC)
68 #define DAT_WALK_ALLOC_CONTINUE (DAT_WALK_CONTINUE | DAT_WALK_ALLOC)
69 #define DAT_WALK_LEAF_ALLOC (DAT_WALK_LEAF | DAT_WALK_ALLOC)
70 
71 union pte {
72 	unsigned long val;
73 	union page_table_entry h;
74 	struct {
75 		unsigned long   :56; /* Hardware bits */
76 		unsigned long u : 1; /* Page unused */
77 		unsigned long s : 1; /* Special */
78 		unsigned long w : 1; /* Writable */
79 		unsigned long r : 1; /* Readable */
80 		unsigned long d : 1; /* Dirty */
81 		unsigned long y : 1; /* Young */
82 		unsigned long sd: 1; /* Soft dirty */
83 		unsigned long pr: 1; /* Present */
84 	} s;
85 	struct {
86 		unsigned char hwbytes[7];
87 		unsigned char swbyte;
88 	};
89 	union {
90 		struct {
91 			unsigned long type :16; /* Token type */
92 			unsigned long par  :16; /* Token parameter */
93 			unsigned long      :20;
94 			unsigned long      : 1; /* Must be 0 */
95 			unsigned long i    : 1; /* Must be 1 */
96 			unsigned long      : 2;
97 			unsigned long      : 7;
98 			unsigned long pr   : 1; /* Must be 0 */
99 		};
100 		struct {
101 			unsigned long token:32; /* Token and parameter */
102 			unsigned long      :32;
103 		};
104 	} tok;
105 };
106 
107 #define _SEGMENT_FR_MASK	(_SEGMENT_MASK >> PAGE_SHIFT)
108 #define _REGION3_FR_MASK	(_REGION3_MASK >> PAGE_SHIFT)
109 #define _PAGES_PER_SEGMENT	_PAGE_ENTRIES
110 #define _PAGES_PER_REGION3	(_PAGES_PER_SEGMENT * _CRST_ENTRIES)
111 
112 /* Soft dirty, needed as macro for atomic operations on ptes */
113 #define _PAGE_SD 0x002
114 
115 /* Needed as macro to perform atomic operations */
116 #define PGSTE_PCL_BIT		0x0080000000000000UL	/* PCL lock, HW bit */
117 #define PGSTE_CMMA_D_BIT	0x0000000000008000UL	/* CMMA dirty soft-bit */
118 
119 enum pgste_gps_usage {
120 	PGSTE_GPS_USAGE_STABLE = 0,
121 	PGSTE_GPS_USAGE_UNUSED,
122 	PGSTE_GPS_USAGE_POT_VOLATILE,
123 	PGSTE_GPS_USAGE_VOLATILE,
124 };
125 
126 union pgste {
127 	unsigned long val;
128 	struct {
129 		unsigned long acc          : 4;
130 		unsigned long fp           : 1;
131 		unsigned long              : 3;
132 		unsigned long pcl          : 1;
133 		unsigned long hr           : 1;
134 		unsigned long hc           : 1;
135 		unsigned long              : 2;
136 		unsigned long gr           : 1;
137 		unsigned long gc           : 1;
138 		unsigned long              : 1;
139 		unsigned long              :16; /* val16 */
140 		unsigned long zero         : 1;
141 		unsigned long nodat        : 1;
142 		unsigned long              : 4;
143 		unsigned long usage        : 2;
144 		unsigned long              : 8;
145 		unsigned long cmma_d       : 1; /* Dirty flag for CMMA bits */
146 		unsigned long prefix_notif : 1; /* Guest prefix invalidation notification */
147 		unsigned long vsie_notif   : 1; /* Referenced in a shadow table */
148 		unsigned long              : 5;
149 		unsigned long              : 8;
150 	};
151 	struct {
152 		unsigned short hwbytes0;
153 		unsigned short val16;	/* Used to store chunked values, see dat_{s,g}et_ptval() */
154 		unsigned short hwbytes4;
155 		unsigned char flags;	/* Maps to the software bits */
156 		unsigned char hwbyte7;
157 	} __packed;
158 };
159 
160 union pmd {
161 	unsigned long val;
162 	union segment_table_entry h;
163 	struct {
164 		struct {
165 			unsigned long              :44; /* HW */
166 			unsigned long              : 3; /* Unused */
167 			unsigned long              : 1; /* HW */
168 			unsigned long s            : 1; /* Special */
169 			unsigned long w            : 1; /* Writable soft-bit */
170 			unsigned long r            : 1; /* Readable soft-bit */
171 			unsigned long d            : 1; /* Dirty */
172 			unsigned long y            : 1; /* Young */
173 			unsigned long              : 3; /* HW */
174 			unsigned long prefix_notif : 1; /* Guest prefix invalidation notification */
175 			unsigned long vsie_notif   : 1; /* Referenced in a shadow table */
176 			unsigned long              : 4; /* HW */
177 			unsigned long sd           : 1; /* Soft-Dirty */
178 			unsigned long pr           : 1; /* Present */
179 		} fc1;
180 	} s;
181 };
182 
183 union pud {
184 	unsigned long val;
185 	union region3_table_entry h;
186 	struct {
187 		struct {
188 			unsigned long              :33; /* HW */
189 			unsigned long              :14; /* Unused */
190 			unsigned long              : 1; /* HW */
191 			unsigned long s            : 1; /* Special */
192 			unsigned long w            : 1; /* Writable soft-bit */
193 			unsigned long r            : 1; /* Readable soft-bit */
194 			unsigned long d            : 1; /* Dirty */
195 			unsigned long y            : 1; /* Young */
196 			unsigned long              : 3; /* HW */
197 			unsigned long prefix_notif : 1; /* Guest prefix invalidation notification */
198 			unsigned long vsie_notif   : 1; /* Referenced in a shadow table */
199 			unsigned long              : 4; /* HW */
200 			unsigned long sd           : 1; /* Soft-Dirty */
201 			unsigned long pr           : 1; /* Present */
202 		} fc1;
203 	} s;
204 };
205 
206 union p4d {
207 	unsigned long val;
208 	union region2_table_entry h;
209 };
210 
211 union pgd {
212 	unsigned long val;
213 	union region1_table_entry h;
214 };
215 
216 union crste {
217 	unsigned long val;
218 	union {
219 		struct {
220 			unsigned long   :52;
221 			unsigned long   : 1;
222 			unsigned long fc: 1;
223 			unsigned long p : 1;
224 			unsigned long   : 1;
225 			unsigned long   : 2;
226 			unsigned long i : 1;
227 			unsigned long   : 1;
228 			unsigned long tt: 2;
229 			unsigned long   : 2;
230 		};
231 		struct {
232 			unsigned long to:52;
233 			unsigned long   : 1;
234 			unsigned long fc: 1;
235 			unsigned long p : 1;
236 			unsigned long   : 1;
237 			unsigned long tf: 2;
238 			unsigned long i : 1;
239 			unsigned long   : 1;
240 			unsigned long tt: 2;
241 			unsigned long tl: 2;
242 		} fc0;
243 		struct {
244 			unsigned long    :47;
245 			unsigned long av : 1; /* ACCF-Validity Control */
246 			unsigned long acc: 4; /* Access-Control Bits */
247 			unsigned long f  : 1; /* Fetch-Protection Bit */
248 			unsigned long fc : 1; /* Format-Control */
249 			unsigned long p  : 1; /* DAT-Protection Bit */
250 			unsigned long iep: 1; /* Instruction-Execution-Protection */
251 			unsigned long    : 2;
252 			unsigned long i  : 1; /* Segment-Invalid Bit */
253 			unsigned long cs : 1; /* Common-Segment Bit */
254 			unsigned long tt : 2; /* Table-Type Bits */
255 			unsigned long    : 2;
256 		} fc1;
257 	} h;
258 	struct {
259 		struct {
260 			unsigned long              :47;
261 			unsigned long              : 1; /* HW (should be 0) */
262 			unsigned long s            : 1; /* Special */
263 			unsigned long w            : 1; /* Writable */
264 			unsigned long r            : 1; /* Readable */
265 			unsigned long d            : 1; /* Dirty */
266 			unsigned long y            : 1; /* Young */
267 			unsigned long              : 3; /* HW */
268 			unsigned long prefix_notif : 1; /* Guest prefix invalidation notification */
269 			unsigned long vsie_notif   : 1; /* Referenced in a shadow table */
270 			unsigned long              : 4; /* HW */
271 			unsigned long sd           : 1; /* Soft-Dirty */
272 			unsigned long pr           : 1; /* Present */
273 		} fc1;
274 	} s;
275 	union {
276 		struct {
277 			unsigned long type :16; /* Token type */
278 			unsigned long par  :16; /* Token parameter */
279 			unsigned long      :26;
280 			unsigned long i    : 1; /* Must be 1 */
281 			unsigned long      : 1;
282 			unsigned long tt   : 2;
283 			unsigned long      : 1;
284 			unsigned long pr   : 1; /* Must be 0 */
285 		};
286 		struct {
287 			unsigned long token:32; /* Token and parameter */
288 			unsigned long      :32;
289 		};
290 	} tok;
291 	union pmd pmd;
292 	union pud pud;
293 	union p4d p4d;
294 	union pgd pgd;
295 };
296 
297 union skey {
298 	unsigned char skey;
299 	struct {
300 		unsigned char acc :4;
301 		unsigned char fp  :1;
302 		unsigned char r   :1;
303 		unsigned char c   :1;
304 		unsigned char zero:1;
305 	};
306 };
307 
308 static_assert(sizeof(union pgste) == sizeof(unsigned long));
309 static_assert(sizeof(union pte) == sizeof(unsigned long));
310 static_assert(sizeof(union pmd) == sizeof(unsigned long));
311 static_assert(sizeof(union pud) == sizeof(unsigned long));
312 static_assert(sizeof(union p4d) == sizeof(unsigned long));
313 static_assert(sizeof(union pgd) == sizeof(unsigned long));
314 static_assert(sizeof(union crste) == sizeof(unsigned long));
315 static_assert(sizeof(union skey) == sizeof(char));
316 
317 struct segment_table {
318 	union pmd pmds[_CRST_ENTRIES];
319 };
320 
321 struct region3_table {
322 	union pud puds[_CRST_ENTRIES];
323 };
324 
325 struct region2_table {
326 	union p4d p4ds[_CRST_ENTRIES];
327 };
328 
329 struct region1_table {
330 	union pgd pgds[_CRST_ENTRIES];
331 };
332 
333 struct crst_table {
334 	union {
335 		union crste crstes[_CRST_ENTRIES];
336 		struct segment_table segment;
337 		struct region3_table region3;
338 		struct region2_table region2;
339 		struct region1_table region1;
340 	};
341 };
342 
343 struct page_table {
344 	union pte ptes[_PAGE_ENTRIES];
345 	union pgste pgstes[_PAGE_ENTRIES];
346 };
347 
348 static_assert(sizeof(struct crst_table) == _CRST_TABLE_SIZE);
349 static_assert(sizeof(struct page_table) == PAGE_SIZE);
350 
351 struct dat_walk;
352 
353 typedef long (*dat_walk_op)(union crste *crste, gfn_t gfn, gfn_t next, struct dat_walk *w);
354 
355 struct dat_walk_ops {
356 	union {
357 		dat_walk_op crste_ops[4];
358 		struct {
359 			dat_walk_op pmd_entry;
360 			dat_walk_op pud_entry;
361 			dat_walk_op p4d_entry;
362 			dat_walk_op pgd_entry;
363 		};
364 	};
365 	long (*pte_entry)(union pte *pte, gfn_t gfn, gfn_t next, struct dat_walk *w);
366 };
367 
368 struct dat_walk {
369 	const struct dat_walk_ops *ops;
370 	union crste *last;
371 	union pte *last_pte;
372 	union asce asce;
373 	gfn_t start;
374 	gfn_t end;
375 	int flags;
376 	void *priv;
377 };
378 
379 struct ptval_param {
380 	unsigned char offset : 6;
381 	unsigned char len : 2;
382 };
383 
384 /**
385  * _pte() - Useful constructor for union pte
386  * @pfn: the pfn this pte should point to.
387  * @writable: whether the pte should be writable.
388  * @dirty: whether the pte should be dirty.
389  * @special: whether the pte should be marked as special
390  *
391  * The pte is also marked as young and present. If the pte is marked as dirty,
392  * it gets marked as soft-dirty too. If the pte is not dirty, the hardware
393  * protect bit is set (independently of the write softbit); this way proper
394  * dirty tracking can be performed.
395  *
396  * Return: a union pte value.
397  */
398 static inline union pte _pte(kvm_pfn_t pfn, bool writable, bool dirty, bool special)
399 {
400 	union pte res = { .val = PFN_PHYS(pfn) };
401 
402 	res.h.p = !dirty;
403 	res.s.y = 1;
404 	res.s.pr = 1;
405 	res.s.w = writable;
406 	res.s.d = dirty;
407 	res.s.sd = dirty;
408 	res.s.s = special;
409 	return res;
410 }
411 
412 static inline union crste _crste_fc0(kvm_pfn_t pfn, int tt)
413 {
414 	union crste res = { .val = PFN_PHYS(pfn) };
415 
416 	res.h.tt = tt;
417 	res.h.fc0.tl = _REGION_ENTRY_LENGTH;
418 	res.h.fc0.tf = 0;
419 	return res;
420 }
421 
422 /**
423  * _crste() - Useful constructor for union crste with FC=1
424  * @pfn: the pfn this pte should point to.
425  * @tt: the table type
426  * @writable: whether the pte should be writable.
427  * @dirty: whether the pte should be dirty.
428  *
429  * The crste is also marked as young and present. If the crste is marked as
430  * dirty, it gets marked as soft-dirty too. If the crste is not dirty, the
431  * hardware protect bit is set (independently of the write softbit); this way
432  * proper dirty tracking can be performed.
433  *
434  * Return: a union crste value.
435  */
436 static inline union crste _crste_fc1(kvm_pfn_t pfn, int tt, bool writable, bool dirty)
437 {
438 	union crste res = { .val = PFN_PHYS(pfn) & _SEGMENT_MASK };
439 
440 	res.h.tt = tt;
441 	res.h.p = !dirty;
442 	res.h.fc = 1;
443 	res.s.fc1.y = 1;
444 	res.s.fc1.pr = 1;
445 	res.s.fc1.w = writable;
446 	res.s.fc1.d = dirty;
447 	res.s.fc1.sd = dirty;
448 	return res;
449 }
450 
451 union essa_state {
452 	unsigned char val;
453 	struct {
454 		unsigned char		: 2;
455 		unsigned char nodat	: 1;
456 		unsigned char exception	: 1;
457 		unsigned char usage	: 2;
458 		unsigned char content	: 2;
459 	};
460 };
461 
462 /**
463  * struct vsie_rmap - reverse mapping for shadow page table entries
464  * @next: pointer to next rmap in the list
465  * @r_gfn: virtual rmap address in the shadow guest address space
466  */
467 struct vsie_rmap {
468 	struct vsie_rmap *next;
469 	union {
470 		unsigned long val;
471 		struct {
472 			long          level: 8;
473 			unsigned long      : 4;
474 			unsigned long r_gfn:52;
475 		};
476 	};
477 };
478 
479 static_assert(sizeof(struct vsie_rmap) == 2 * sizeof(long));
480 
481 #define KVM_S390_MMU_CACHE_N_CRSTS	6
482 #define KVM_S390_MMU_CACHE_N_PTS	2
483 #define KVM_S390_MMU_CACHE_N_RMAPS	16
484 struct kvm_s390_mmu_cache {
485 	void *crsts[KVM_S390_MMU_CACHE_N_CRSTS];
486 	void *pts[KVM_S390_MMU_CACHE_N_PTS];
487 	void *rmaps[KVM_S390_MMU_CACHE_N_RMAPS];
488 	short int n_crsts;
489 	short int n_pts;
490 	short int n_rmaps;
491 };
492 
493 struct guest_fault {
494 	gfn_t gfn;		/* Guest frame */
495 	kvm_pfn_t pfn;		/* Host PFN */
496 	struct page *page;	/* Host page */
497 	union pte *ptep;	/* Used to resolve the fault, or NULL */
498 	union crste *crstep;	/* Used to resolve the fault, or NULL */
499 	bool writable;		/* Mapping is writable */
500 	bool write_attempt;	/* Write access attempted */
501 	bool attempt_pfault;	/* Attempt a pfault first */
502 	bool valid;		/* This entry contains valid data */
503 	void (*callback)(struct guest_fault *f);
504 	void *priv;
505 };
506 
507 /*
508  *	0	1	2	3	4	5	6	7
509  *	+-------+-------+-------+-------+-------+-------+-------+-------+
510  *  0	|				|	    PGT_ADDR		|
511  *  8	|	 VMADDR		|					|
512  * 16	|								|
513  * 24	|								|
514  */
515 #define MKPTVAL(o, l) ((struct ptval_param) { .offset = (o), .len = ((l) + 1) / 2 - 1})
516 #define PTVAL_PGT_ADDR	MKPTVAL(4, 8)
517 #define PTVAL_VMADDR	MKPTVAL(8, 6)
518 
519 union pgste __must_check __dat_ptep_xchg(union pte *ptep, union pgste pgste, union pte new,
520 					 gfn_t gfn, union asce asce, bool uses_skeys);
521 bool dat_crstep_xchg_atomic(union crste *crstep, union crste old, union crste new, gfn_t gfn,
522 			    union asce asce);
523 void dat_crstep_xchg(union crste *crstep, union crste new, gfn_t gfn, union asce asce);
524 
525 long _dat_walk_gfn_range(gfn_t start, gfn_t end, union asce asce,
526 			 const struct dat_walk_ops *ops, int flags, void *priv);
527 
528 int dat_entry_walk(struct kvm_s390_mmu_cache *mc, gfn_t gfn, union asce asce, int flags,
529 		   int walk_level, union crste **last, union pte **ptepp);
530 void dat_free_level(struct crst_table *table, bool owns_ptes);
531 struct crst_table *dat_alloc_crst_sleepable(unsigned long init);
532 int dat_set_asce_limit(struct kvm_s390_mmu_cache *mc, union asce *asce, int newtype);
533 int dat_get_storage_key(union asce asce, gfn_t gfn, union skey *skey);
534 int dat_set_storage_key(struct kvm_s390_mmu_cache *mc, union asce asce, gfn_t gfn,
535 			union skey skey, bool nq);
536 int dat_cond_set_storage_key(struct kvm_s390_mmu_cache *mmc, union asce asce, gfn_t gfn,
537 			     union skey skey, union skey *oldkey, bool nq, bool mr, bool mc);
538 int dat_reset_reference_bit(union asce asce, gfn_t gfn);
539 long dat_reset_skeys(union asce asce, gfn_t start);
540 
541 unsigned long dat_get_ptval(struct page_table *table, struct ptval_param param);
542 void dat_set_ptval(struct page_table *table, struct ptval_param param, unsigned long val);
543 
544 int dat_set_slot(struct kvm_s390_mmu_cache *mc, union asce asce, gfn_t start, gfn_t end,
545 		 u16 type, u16 param);
546 int dat_set_prefix_notif_bit(union asce asce, gfn_t gfn);
547 bool dat_test_age_gfn(union asce asce, gfn_t start, gfn_t end);
548 
549 int dat_perform_essa(union asce asce, gfn_t gfn, int orc, union essa_state *state, bool *dirty);
550 long dat_reset_cmma(union asce asce, gfn_t start_gfn);
551 int dat_peek_cmma(gfn_t start, union asce asce, unsigned int *count, u8 *values);
552 int dat_get_cmma(union asce asce, gfn_t *start, unsigned int *count, u8 *values, atomic64_t *rem);
553 int dat_set_cmma_bits(struct kvm_s390_mmu_cache *mc, union asce asce, gfn_t gfn,
554 		      unsigned long count, unsigned long mask, const uint8_t *bits);
555 
556 int kvm_s390_mmu_cache_topup(struct kvm_s390_mmu_cache *mc);
557 
558 #define GFP_KVM_S390_MMU_CACHE (GFP_ATOMIC | __GFP_ACCOUNT | __GFP_NOWARN)
559 
560 static inline struct page_table *kvm_s390_mmu_cache_alloc_pt(struct kvm_s390_mmu_cache *mc)
561 {
562 	if (mc->n_pts)
563 		return mc->pts[--mc->n_pts];
564 	return (void *)__get_free_page(GFP_KVM_S390_MMU_CACHE);
565 }
566 
567 static inline struct crst_table *kvm_s390_mmu_cache_alloc_crst(struct kvm_s390_mmu_cache *mc)
568 {
569 	if (mc->n_crsts)
570 		return mc->crsts[--mc->n_crsts];
571 	return (void *)__get_free_pages(GFP_KVM_S390_MMU_CACHE | __GFP_COMP, CRST_ALLOC_ORDER);
572 }
573 
574 static inline struct vsie_rmap *kvm_s390_mmu_cache_alloc_rmap(struct kvm_s390_mmu_cache *mc)
575 {
576 	if (mc->n_rmaps)
577 		return mc->rmaps[--mc->n_rmaps];
578 	return kzalloc_obj(struct vsie_rmap, GFP_KVM_S390_MMU_CACHE);
579 }
580 
581 static inline struct crst_table *crste_table_start(union crste *crstep)
582 {
583 	return (struct crst_table *)ALIGN_DOWN((unsigned long)crstep, _CRST_TABLE_SIZE);
584 }
585 
586 static inline struct page_table *pte_table_start(union pte *ptep)
587 {
588 	return (struct page_table *)ALIGN_DOWN((unsigned long)ptep, _PAGE_TABLE_SIZE);
589 }
590 
591 static inline bool crdte_crste(union crste *crstep, union crste old, union crste new, gfn_t gfn,
592 			       union asce asce)
593 {
594 	unsigned long dtt = 0x10 | new.h.tt << 2;
595 	void *table = crste_table_start(crstep);
596 
597 	return crdte(old.val, new.val, table, dtt, gfn_to_gpa(gfn), asce.val);
598 }
599 
600 /**
601  * idte_crste() - invalidate a crste entry using idte
602  * @crstep: pointer to the crste to be invalidated
603  * @gfn: a gfn mapped by the crste
604  * @opt: options for the idte instruction
605  * @asce: the asce
606  * @local: whether the operation is cpu-local
607  */
608 static __always_inline void idte_crste(union crste *crstep, gfn_t gfn, unsigned long opt,
609 				       union asce asce, int local)
610 {
611 	unsigned long table_origin = __pa(crste_table_start(crstep));
612 	unsigned long gaddr = gfn_to_gpa(gfn) & HPAGE_MASK;
613 
614 	if (__builtin_constant_p(opt) && opt == 0) {
615 		/* flush without guest asce */
616 		asm volatile("idte	%[table_origin],0,%[gaddr],%[local]"
617 			: "+m" (*crstep)
618 			: [table_origin] "a" (table_origin), [gaddr] "a" (gaddr),
619 			  [local] "i" (local)
620 			: "cc");
621 	} else {
622 		/* flush with guest asce */
623 		asm volatile("idte %[table_origin],%[asce],%[gaddr_opt],%[local]"
624 			: "+m" (*crstep)
625 			: [table_origin] "a" (table_origin), [gaddr_opt] "a" (gaddr | opt),
626 			  [asce] "a" (asce.val), [local] "i" (local)
627 			: "cc");
628 	}
629 }
630 
631 static inline void dat_init_pgstes(struct page_table *pt, unsigned long val)
632 {
633 	memset64((void *)pt->pgstes, val, PTRS_PER_PTE);
634 }
635 
636 static inline void dat_init_page_table(struct page_table *pt, unsigned long ptes,
637 				       unsigned long pgstes)
638 {
639 	memset64((void *)pt->ptes, ptes, PTRS_PER_PTE);
640 	dat_init_pgstes(pt, pgstes);
641 }
642 
643 static inline gfn_t asce_end(union asce asce)
644 {
645 	return 1ULL << ((asce.dt + 1) * 11 + _SEGMENT_SHIFT - PAGE_SHIFT);
646 }
647 
648 #define _CRSTE(x) ((union crste) { .val = _Generic((x),	\
649 			union pgd : (x).val,		\
650 			union p4d : (x).val,		\
651 			union pud : (x).val,		\
652 			union pmd : (x).val,		\
653 			union crste : (x).val)})
654 
655 #define _CRSTEP(x) ((union crste *)_Generic((*(x)),	\
656 				union pgd : (x),	\
657 				union p4d : (x),	\
658 				union pud : (x),	\
659 				union pmd : (x),	\
660 				union crste : (x)))
661 
662 #define _CRSTP(x) ((struct crst_table *)_Generic((*(x)),	\
663 		struct crst_table : (x),			\
664 		struct segment_table : (x),			\
665 		struct region3_table : (x),			\
666 		struct region2_table : (x),			\
667 		struct region1_table : (x)))
668 
669 static inline bool asce_contains_gfn(union asce asce, gfn_t gfn)
670 {
671 	return gfn < asce_end(asce);
672 }
673 
674 static inline bool is_pmd(union crste crste)
675 {
676 	return crste.h.tt == TABLE_TYPE_SEGMENT;
677 }
678 
679 static inline bool is_pud(union crste crste)
680 {
681 	return crste.h.tt == TABLE_TYPE_REGION3;
682 }
683 
684 static inline bool is_p4d(union crste crste)
685 {
686 	return crste.h.tt == TABLE_TYPE_REGION2;
687 }
688 
689 static inline bool is_pgd(union crste crste)
690 {
691 	return crste.h.tt == TABLE_TYPE_REGION1;
692 }
693 
694 static inline phys_addr_t pmd_origin_large(union pmd pmd)
695 {
696 	return pmd.val & _SEGMENT_ENTRY_ORIGIN_LARGE;
697 }
698 
699 static inline phys_addr_t pud_origin_large(union pud pud)
700 {
701 	return pud.val & _REGION3_ENTRY_ORIGIN_LARGE;
702 }
703 
704 /**
705  * crste_origin_large() - Return the large frame origin of a large crste
706  * @crste: The crste whose origin is to be returned. Should be either a
707  *         region-3 table entry or a segment table entry, in both cases with
708  *         FC set to 1 (large pages).
709  *
710  * Return: The origin of the large frame pointed to by @crste, or -1 if the
711  *         crste was not large (wrong table type, or FC==0)
712  */
713 static inline phys_addr_t crste_origin_large(union crste crste)
714 {
715 	if (unlikely(!crste.h.fc || crste.h.tt > TABLE_TYPE_REGION3))
716 		return -1;
717 	if (is_pmd(crste))
718 		return pmd_origin_large(crste.pmd);
719 	return pud_origin_large(crste.pud);
720 }
721 
722 #define crste_origin(x) (_Generic((x),				\
723 		union pmd : (x).val & _SEGMENT_ENTRY_ORIGIN,	\
724 		union pud : (x).val & _REGION_ENTRY_ORIGIN,	\
725 		union p4d : (x).val & _REGION_ENTRY_ORIGIN,	\
726 		union pgd : (x).val & _REGION_ENTRY_ORIGIN))
727 
728 static inline unsigned long pte_origin(union pte pte)
729 {
730 	return pte.val & PAGE_MASK;
731 }
732 
733 static inline bool pmd_prefix(union pmd pmd)
734 {
735 	return pmd.h.fc && pmd.s.fc1.prefix_notif;
736 }
737 
738 static inline bool pud_prefix(union pud pud)
739 {
740 	return pud.h.fc && pud.s.fc1.prefix_notif;
741 }
742 
743 static inline bool crste_leaf(union crste crste)
744 {
745 	return (crste.h.tt <= TABLE_TYPE_REGION3) && crste.h.fc;
746 }
747 
748 static inline bool crste_prefix(union crste crste)
749 {
750 	return crste_leaf(crste) && crste.s.fc1.prefix_notif;
751 }
752 
753 static inline bool crste_dirty(union crste crste)
754 {
755 	return crste_leaf(crste) && crste.s.fc1.d;
756 }
757 
758 static inline union pgste *pgste_of(union pte *pte)
759 {
760 	return (union pgste *)(pte + _PAGE_ENTRIES);
761 }
762 
763 static inline bool pte_hole(union pte pte)
764 {
765 	return pte.h.i && !pte.tok.pr && pte.tok.type != _DAT_TOKEN_NONE;
766 }
767 
768 static inline bool _crste_hole(union crste crste)
769 {
770 	return crste.h.i && !crste.tok.pr && crste.tok.type != _DAT_TOKEN_NONE;
771 }
772 
773 #define crste_hole(x) _crste_hole(_CRSTE(x))
774 
775 static inline bool _crste_none(union crste crste)
776 {
777 	return crste.h.i && !crste.tok.pr && crste.tok.type == _DAT_TOKEN_NONE;
778 }
779 
780 #define crste_none(x) _crste_none(_CRSTE(x))
781 
782 static inline phys_addr_t large_pud_to_phys(union pud pud, gfn_t gfn)
783 {
784 	return pud_origin_large(pud) | (gfn_to_gpa(gfn) & ~_REGION3_MASK);
785 }
786 
787 static inline phys_addr_t large_pmd_to_phys(union pmd pmd, gfn_t gfn)
788 {
789 	return pmd_origin_large(pmd) | (gfn_to_gpa(gfn) & ~_SEGMENT_MASK);
790 }
791 
792 static inline phys_addr_t large_crste_to_phys(union crste crste, gfn_t gfn)
793 {
794 	if (unlikely(!crste.h.fc || crste.h.tt > TABLE_TYPE_REGION3))
795 		return -1;
796 	if (is_pmd(crste))
797 		return large_pmd_to_phys(crste.pmd, gfn);
798 	return large_pud_to_phys(crste.pud, gfn);
799 }
800 
801 static inline bool cspg_crste(union crste *crstep, union crste old, union crste new)
802 {
803 	return cspg(&crstep->val, old.val, new.val);
804 }
805 
806 static inline struct page_table *dereference_pmd(union pmd pmd)
807 {
808 	return phys_to_virt(crste_origin(pmd));
809 }
810 
811 static inline struct segment_table *dereference_pud(union pud pud)
812 {
813 	return phys_to_virt(crste_origin(pud));
814 }
815 
816 static inline struct region3_table *dereference_p4d(union p4d p4d)
817 {
818 	return phys_to_virt(crste_origin(p4d));
819 }
820 
821 static inline struct region2_table *dereference_pgd(union pgd pgd)
822 {
823 	return phys_to_virt(crste_origin(pgd));
824 }
825 
826 static inline struct crst_table *_dereference_crste(union crste crste)
827 {
828 	if (unlikely(is_pmd(crste)))
829 		return NULL;
830 	return phys_to_virt(crste_origin(crste.pud));
831 }
832 
833 #define dereference_crste(x) (_Generic((x),			\
834 		union pud : _dereference_crste(_CRSTE(x)),	\
835 		union p4d : _dereference_crste(_CRSTE(x)),	\
836 		union pgd : _dereference_crste(_CRSTE(x)),	\
837 		union crste : _dereference_crste(_CRSTE(x))))
838 
839 static inline struct crst_table *dereference_asce(union asce asce)
840 {
841 	return phys_to_virt(asce.val & _ASCE_ORIGIN);
842 }
843 
844 static inline void asce_flush_tlb(union asce asce)
845 {
846 	__tlb_flush_idte(asce.val);
847 }
848 
849 static inline bool pgste_get_trylock(union pte *ptep, union pgste *res)
850 {
851 	union pgste *pgstep = pgste_of(ptep);
852 	union pgste old_pgste;
853 
854 	if (READ_ONCE(pgstep->val) & PGSTE_PCL_BIT)
855 		return false;
856 	old_pgste.val = __atomic64_or_barrier(PGSTE_PCL_BIT, &pgstep->val);
857 	if (old_pgste.pcl)
858 		return false;
859 	old_pgste.pcl = 1;
860 	*res = old_pgste;
861 	return true;
862 }
863 
864 static inline union pgste pgste_get_lock(union pte *ptep)
865 {
866 	union pgste res;
867 
868 	while (!pgste_get_trylock(ptep, &res))
869 		cpu_relax();
870 	return res;
871 }
872 
873 static inline void pgste_set_unlock(union pte *ptep, union pgste pgste)
874 {
875 	pgste.pcl = 0;
876 	barrier();
877 	WRITE_ONCE(*pgste_of(ptep), pgste);
878 }
879 
880 static inline void dat_ptep_xchg(union pte *ptep, union pte new, gfn_t gfn, union asce asce,
881 				 bool has_skeys)
882 {
883 	union pgste pgste;
884 
885 	pgste = pgste_get_lock(ptep);
886 	pgste = __dat_ptep_xchg(ptep, pgste, new, gfn, asce, has_skeys);
887 	pgste_set_unlock(ptep, pgste);
888 }
889 
890 static inline void dat_ptep_clear(union pte *ptep, gfn_t gfn, union asce asce, bool has_skeys)
891 {
892 	dat_ptep_xchg(ptep, _PTE_EMPTY, gfn, asce, has_skeys);
893 }
894 
895 static inline void dat_free_pt(struct page_table *pt)
896 {
897 	free_page((unsigned long)pt);
898 }
899 
900 static inline void _dat_free_crst(struct crst_table *table)
901 {
902 	free_pages((unsigned long)table, CRST_ALLOC_ORDER);
903 }
904 
905 #define dat_free_crst(x) _dat_free_crst(_CRSTP(x))
906 
907 static inline void kvm_s390_free_mmu_cache(struct kvm_s390_mmu_cache *mc)
908 {
909 	if (!mc)
910 		return;
911 	while (mc->n_pts)
912 		dat_free_pt(mc->pts[--mc->n_pts]);
913 	while (mc->n_crsts)
914 		_dat_free_crst(mc->crsts[--mc->n_crsts]);
915 	while (mc->n_rmaps)
916 		kfree(mc->rmaps[--mc->n_rmaps]);
917 	kfree(mc);
918 }
919 
920 DEFINE_FREE(kvm_s390_mmu_cache, struct kvm_s390_mmu_cache *, if (_T) kvm_s390_free_mmu_cache(_T))
921 
922 static inline struct kvm_s390_mmu_cache *kvm_s390_new_mmu_cache(void)
923 {
924 	struct kvm_s390_mmu_cache *mc __free(kvm_s390_mmu_cache) = NULL;
925 
926 	mc = kzalloc_obj(*mc, GFP_KERNEL_ACCOUNT);
927 	if (mc && !kvm_s390_mmu_cache_topup(mc))
928 		return_ptr(mc);
929 	return NULL;
930 }
931 
932 static inline bool dat_pmdp_xchg_atomic(union pmd *pmdp, union pmd old, union pmd new,
933 					gfn_t gfn, union asce asce)
934 {
935 	return dat_crstep_xchg_atomic(_CRSTEP(pmdp), _CRSTE(old), _CRSTE(new), gfn, asce);
936 }
937 
938 static inline bool dat_pudp_xchg_atomic(union pud *pudp, union pud old, union pud new,
939 					gfn_t gfn, union asce asce)
940 {
941 	return dat_crstep_xchg_atomic(_CRSTEP(pudp), _CRSTE(old), _CRSTE(new), gfn, asce);
942 }
943 
944 static inline union crste dat_crstep_clear_atomic(union crste *crstep, gfn_t gfn, union asce asce)
945 {
946 	union crste oldcrste, empty = _CRSTE_EMPTY(crstep->h.tt);
947 
948 	do {
949 		oldcrste = READ_ONCE(*crstep);
950 	} while (!dat_crstep_xchg_atomic(crstep, oldcrste, empty, gfn, asce));
951 	return oldcrste;
952 }
953 
954 static inline int get_level(union crste *crstep, union pte *ptep)
955 {
956 	return ptep ? TABLE_TYPE_PAGE_TABLE : crstep->h.tt;
957 }
958 
959 static inline int dat_delete_slot(struct kvm_s390_mmu_cache *mc, union asce asce, gfn_t start,
960 				  unsigned long npages)
961 {
962 	return dat_set_slot(mc, asce, start, start + npages, _DAT_TOKEN_PIC, PGM_ADDRESSING);
963 }
964 
965 static inline int dat_create_slot(struct kvm_s390_mmu_cache *mc, union asce asce, gfn_t start,
966 				  unsigned long npages)
967 {
968 	return dat_set_slot(mc, asce, start, start + npages, _DAT_TOKEN_NONE, 0);
969 }
970 
971 static inline bool crste_is_ucas(union crste crste)
972 {
973 	return is_pmd(crste) && crste.h.i && crste.h.fc0.tl == 1 && crste.h.fc == 0;
974 }
975 
976 #endif /* __KVM_S390_DAT_H */
977