xref: /linux/arch/s390/kvm/dat.h (revision 8934827db5403eae57d4537114a9ff88b0a8460f)
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 /* Soft dirty, needed as macro for atomic operations on ptes */
108 #define _PAGE_SD 0x002
109 
110 /* Needed as macro to perform atomic operations */
111 #define PGSTE_PCL_BIT		0x0080000000000000UL	/* PCL lock, HW bit */
112 #define PGSTE_CMMA_D_BIT	0x0000000000008000UL	/* CMMA dirty soft-bit */
113 
114 enum pgste_gps_usage {
115 	PGSTE_GPS_USAGE_STABLE = 0,
116 	PGSTE_GPS_USAGE_UNUSED,
117 	PGSTE_GPS_USAGE_POT_VOLATILE,
118 	PGSTE_GPS_USAGE_VOLATILE,
119 };
120 
121 union pgste {
122 	unsigned long val;
123 	struct {
124 		unsigned long acc          : 4;
125 		unsigned long fp           : 1;
126 		unsigned long              : 3;
127 		unsigned long pcl          : 1;
128 		unsigned long hr           : 1;
129 		unsigned long hc           : 1;
130 		unsigned long              : 2;
131 		unsigned long gr           : 1;
132 		unsigned long gc           : 1;
133 		unsigned long              : 1;
134 		unsigned long              :16; /* val16 */
135 		unsigned long zero         : 1;
136 		unsigned long nodat        : 1;
137 		unsigned long              : 4;
138 		unsigned long usage        : 2;
139 		unsigned long              : 8;
140 		unsigned long cmma_d       : 1; /* Dirty flag for CMMA bits */
141 		unsigned long prefix_notif : 1; /* Guest prefix invalidation notification */
142 		unsigned long vsie_notif   : 1; /* Referenced in a shadow table */
143 		unsigned long              : 5;
144 		unsigned long              : 8;
145 	};
146 	struct {
147 		unsigned short hwbytes0;
148 		unsigned short val16;	/* Used to store chunked values, see dat_{s,g}et_ptval() */
149 		unsigned short hwbytes4;
150 		unsigned char flags;	/* Maps to the software bits */
151 		unsigned char hwbyte7;
152 	} __packed;
153 };
154 
155 union pmd {
156 	unsigned long val;
157 	union segment_table_entry h;
158 	struct {
159 		struct {
160 			unsigned long              :44; /* HW */
161 			unsigned long              : 3; /* Unused */
162 			unsigned long              : 1; /* HW */
163 			unsigned long w            : 1; /* Writable soft-bit */
164 			unsigned long r            : 1; /* Readable soft-bit */
165 			unsigned long d            : 1; /* Dirty */
166 			unsigned long y            : 1; /* Young */
167 			unsigned long prefix_notif : 1; /* Guest prefix invalidation notification */
168 			unsigned long              : 3; /* HW */
169 			unsigned long vsie_notif   : 1; /* Referenced in a shadow table */
170 			unsigned long              : 1; /* Unused */
171 			unsigned long              : 4; /* HW */
172 			unsigned long sd           : 1; /* Soft-Dirty */
173 			unsigned long pr           : 1; /* Present */
174 		} fc1;
175 	} s;
176 };
177 
178 union pud {
179 	unsigned long val;
180 	union region3_table_entry h;
181 	struct {
182 		struct {
183 			unsigned long              :33; /* HW */
184 			unsigned long              :14; /* Unused */
185 			unsigned long              : 1; /* HW */
186 			unsigned long w            : 1; /* Writable soft-bit */
187 			unsigned long r            : 1; /* Readable soft-bit */
188 			unsigned long d            : 1; /* Dirty */
189 			unsigned long y            : 1; /* Young */
190 			unsigned long prefix_notif : 1; /* Guest prefix invalidation notification */
191 			unsigned long              : 3; /* HW */
192 			unsigned long vsie_notif   : 1; /* Referenced in a shadow table */
193 			unsigned long              : 1; /* Unused */
194 			unsigned long              : 4; /* HW */
195 			unsigned long sd           : 1; /* Soft-Dirty */
196 			unsigned long pr           : 1; /* Present */
197 		} fc1;
198 	} s;
199 };
200 
201 union p4d {
202 	unsigned long val;
203 	union region2_table_entry h;
204 };
205 
206 union pgd {
207 	unsigned long val;
208 	union region1_table_entry h;
209 };
210 
211 union crste {
212 	unsigned long val;
213 	union {
214 		struct {
215 			unsigned long   :52;
216 			unsigned long   : 1;
217 			unsigned long fc: 1;
218 			unsigned long p : 1;
219 			unsigned long   : 1;
220 			unsigned long   : 2;
221 			unsigned long i : 1;
222 			unsigned long   : 1;
223 			unsigned long tt: 2;
224 			unsigned long   : 2;
225 		};
226 		struct {
227 			unsigned long to:52;
228 			unsigned long   : 1;
229 			unsigned long fc: 1;
230 			unsigned long p : 1;
231 			unsigned long   : 1;
232 			unsigned long tf: 2;
233 			unsigned long i : 1;
234 			unsigned long   : 1;
235 			unsigned long tt: 2;
236 			unsigned long tl: 2;
237 		} fc0;
238 		struct {
239 			unsigned long    :47;
240 			unsigned long av : 1; /* ACCF-Validity Control */
241 			unsigned long acc: 4; /* Access-Control Bits */
242 			unsigned long f  : 1; /* Fetch-Protection Bit */
243 			unsigned long fc : 1; /* Format-Control */
244 			unsigned long p  : 1; /* DAT-Protection Bit */
245 			unsigned long iep: 1; /* Instruction-Execution-Protection */
246 			unsigned long    : 2;
247 			unsigned long i  : 1; /* Segment-Invalid Bit */
248 			unsigned long cs : 1; /* Common-Segment Bit */
249 			unsigned long tt : 2; /* Table-Type Bits */
250 			unsigned long    : 2;
251 		} fc1;
252 	} h;
253 	struct {
254 		struct {
255 			unsigned long              :47;
256 			unsigned long              : 1; /* HW (should be 0) */
257 			unsigned long w            : 1; /* Writable */
258 			unsigned long r            : 1; /* Readable */
259 			unsigned long d            : 1; /* Dirty */
260 			unsigned long y            : 1; /* Young */
261 			unsigned long prefix_notif : 1; /* Guest prefix invalidation notification */
262 			unsigned long              : 3; /* HW */
263 			unsigned long vsie_notif   : 1; /* Referenced in a shadow table */
264 			unsigned long              : 1;
265 			unsigned long              : 4; /* HW */
266 			unsigned long sd           : 1; /* Soft-Dirty */
267 			unsigned long pr           : 1; /* Present */
268 		} fc1;
269 	} s;
270 	union {
271 		struct {
272 			unsigned long type :16; /* Token type */
273 			unsigned long par  :16; /* Token parameter */
274 			unsigned long      :26;
275 			unsigned long i    : 1; /* Must be 1 */
276 			unsigned long      : 1;
277 			unsigned long tt   : 2;
278 			unsigned long      : 1;
279 			unsigned long pr   : 1; /* Must be 0 */
280 		};
281 		struct {
282 			unsigned long token:32; /* Token and parameter */
283 			unsigned long      :32;
284 		};
285 	} tok;
286 	union pmd pmd;
287 	union pud pud;
288 	union p4d p4d;
289 	union pgd pgd;
290 };
291 
292 union skey {
293 	unsigned char skey;
294 	struct {
295 		unsigned char acc :4;
296 		unsigned char fp  :1;
297 		unsigned char r   :1;
298 		unsigned char c   :1;
299 		unsigned char zero:1;
300 	};
301 };
302 
303 static_assert(sizeof(union pgste) == sizeof(unsigned long));
304 static_assert(sizeof(union pte) == sizeof(unsigned long));
305 static_assert(sizeof(union pmd) == sizeof(unsigned long));
306 static_assert(sizeof(union pud) == sizeof(unsigned long));
307 static_assert(sizeof(union p4d) == sizeof(unsigned long));
308 static_assert(sizeof(union pgd) == sizeof(unsigned long));
309 static_assert(sizeof(union crste) == sizeof(unsigned long));
310 static_assert(sizeof(union skey) == sizeof(char));
311 
312 struct segment_table {
313 	union pmd pmds[_CRST_ENTRIES];
314 };
315 
316 struct region3_table {
317 	union pud puds[_CRST_ENTRIES];
318 };
319 
320 struct region2_table {
321 	union p4d p4ds[_CRST_ENTRIES];
322 };
323 
324 struct region1_table {
325 	union pgd pgds[_CRST_ENTRIES];
326 };
327 
328 struct crst_table {
329 	union {
330 		union crste crstes[_CRST_ENTRIES];
331 		struct segment_table segment;
332 		struct region3_table region3;
333 		struct region2_table region2;
334 		struct region1_table region1;
335 	};
336 };
337 
338 struct page_table {
339 	union pte ptes[_PAGE_ENTRIES];
340 	union pgste pgstes[_PAGE_ENTRIES];
341 };
342 
343 static_assert(sizeof(struct crst_table) == _CRST_TABLE_SIZE);
344 static_assert(sizeof(struct page_table) == PAGE_SIZE);
345 
346 struct dat_walk;
347 
348 typedef long (*dat_walk_op)(union crste *crste, gfn_t gfn, gfn_t next, struct dat_walk *w);
349 
350 struct dat_walk_ops {
351 	union {
352 		dat_walk_op crste_ops[4];
353 		struct {
354 			dat_walk_op pmd_entry;
355 			dat_walk_op pud_entry;
356 			dat_walk_op p4d_entry;
357 			dat_walk_op pgd_entry;
358 		};
359 	};
360 	long (*pte_entry)(union pte *pte, gfn_t gfn, gfn_t next, struct dat_walk *w);
361 };
362 
363 struct dat_walk {
364 	const struct dat_walk_ops *ops;
365 	union crste *last;
366 	union pte *last_pte;
367 	union asce asce;
368 	gfn_t start;
369 	gfn_t end;
370 	int flags;
371 	void *priv;
372 };
373 
374 struct ptval_param {
375 	unsigned char offset : 6;
376 	unsigned char len : 2;
377 };
378 
379 /**
380  * _pte() - Useful constructor for union pte
381  * @pfn: the pfn this pte should point to.
382  * @writable: whether the pte should be writable.
383  * @dirty: whether the pte should be dirty.
384  * @special: whether the pte should be marked as special
385  *
386  * The pte is also marked as young and present. If the pte is marked as dirty,
387  * it gets marked as soft-dirty too. If the pte is not dirty, the hardware
388  * protect bit is set (independently of the write softbit); this way proper
389  * dirty tracking can be performed.
390  *
391  * Return: a union pte value.
392  */
_pte(kvm_pfn_t pfn,bool writable,bool dirty,bool special)393 static inline union pte _pte(kvm_pfn_t pfn, bool writable, bool dirty, bool special)
394 {
395 	union pte res = { .val = PFN_PHYS(pfn) };
396 
397 	res.h.p = !dirty;
398 	res.s.y = 1;
399 	res.s.pr = 1;
400 	res.s.w = writable;
401 	res.s.d = dirty;
402 	res.s.sd = dirty;
403 	res.s.s = special;
404 	return res;
405 }
406 
_crste_fc0(kvm_pfn_t pfn,int tt)407 static inline union crste _crste_fc0(kvm_pfn_t pfn, int tt)
408 {
409 	union crste res = { .val = PFN_PHYS(pfn) };
410 
411 	res.h.tt = tt;
412 	res.h.fc0.tl = _REGION_ENTRY_LENGTH;
413 	res.h.fc0.tf = 0;
414 	return res;
415 }
416 
417 /**
418  * _crste() - Useful constructor for union crste with FC=1
419  * @pfn: the pfn this pte should point to.
420  * @tt: the table type
421  * @writable: whether the pte should be writable.
422  * @dirty: whether the pte should be dirty.
423  *
424  * The crste is also marked as young and present. If the crste is marked as
425  * dirty, it gets marked as soft-dirty too. If the crste is not dirty, the
426  * hardware protect bit is set (independently of the write softbit); this way
427  * proper dirty tracking can be performed.
428  *
429  * Return: a union crste value.
430  */
_crste_fc1(kvm_pfn_t pfn,int tt,bool writable,bool dirty)431 static inline union crste _crste_fc1(kvm_pfn_t pfn, int tt, bool writable, bool dirty)
432 {
433 	union crste res = { .val = PFN_PHYS(pfn) & _SEGMENT_MASK };
434 
435 	res.h.tt = tt;
436 	res.h.p = !dirty;
437 	res.h.fc = 1;
438 	res.s.fc1.y = 1;
439 	res.s.fc1.pr = 1;
440 	res.s.fc1.w = writable;
441 	res.s.fc1.d = dirty;
442 	res.s.fc1.sd = dirty;
443 	return res;
444 }
445 
446 union essa_state {
447 	unsigned char val;
448 	struct {
449 		unsigned char		: 2;
450 		unsigned char nodat	: 1;
451 		unsigned char exception	: 1;
452 		unsigned char usage	: 2;
453 		unsigned char content	: 2;
454 	};
455 };
456 
457 /**
458  * struct vsie_rmap - reverse mapping for shadow page table entries
459  * @next: pointer to next rmap in the list
460  * @r_gfn: virtual rmap address in the shadow guest address space
461  */
462 struct vsie_rmap {
463 	struct vsie_rmap *next;
464 	union {
465 		unsigned long val;
466 		struct {
467 			long          level: 8;
468 			unsigned long      : 4;
469 			unsigned long r_gfn:52;
470 		};
471 	};
472 };
473 
474 static_assert(sizeof(struct vsie_rmap) == 2 * sizeof(long));
475 
476 #define KVM_S390_MMU_CACHE_N_CRSTS	6
477 #define KVM_S390_MMU_CACHE_N_PTS	2
478 #define KVM_S390_MMU_CACHE_N_RMAPS	16
479 struct kvm_s390_mmu_cache {
480 	void *crsts[KVM_S390_MMU_CACHE_N_CRSTS];
481 	void *pts[KVM_S390_MMU_CACHE_N_PTS];
482 	void *rmaps[KVM_S390_MMU_CACHE_N_RMAPS];
483 	short int n_crsts;
484 	short int n_pts;
485 	short int n_rmaps;
486 };
487 
488 struct guest_fault {
489 	gfn_t gfn;		/* Guest frame */
490 	kvm_pfn_t pfn;		/* Host PFN */
491 	struct page *page;	/* Host page */
492 	union pte *ptep;	/* Used to resolve the fault, or NULL */
493 	union crste *crstep;	/* Used to resolve the fault, or NULL */
494 	bool writable;		/* Mapping is writable */
495 	bool write_attempt;	/* Write access attempted */
496 	bool attempt_pfault;	/* Attempt a pfault first */
497 	bool valid;		/* This entry contains valid data */
498 	void (*callback)(struct guest_fault *f);
499 	void *priv;
500 };
501 
502 /*
503  *	0	1	2	3	4	5	6	7
504  *	+-------+-------+-------+-------+-------+-------+-------+-------+
505  *  0	|				|	    PGT_ADDR		|
506  *  8	|	 VMADDR		|					|
507  * 16	|								|
508  * 24	|								|
509  */
510 #define MKPTVAL(o, l) ((struct ptval_param) { .offset = (o), .len = ((l) + 1) / 2 - 1})
511 #define PTVAL_PGT_ADDR	MKPTVAL(4, 8)
512 #define PTVAL_VMADDR	MKPTVAL(8, 6)
513 
514 union pgste __must_check __dat_ptep_xchg(union pte *ptep, union pgste pgste, union pte new,
515 					 gfn_t gfn, union asce asce, bool uses_skeys);
516 bool dat_crstep_xchg_atomic(union crste *crstep, union crste old, union crste new, gfn_t gfn,
517 			    union asce asce);
518 void dat_crstep_xchg(union crste *crstep, union crste new, gfn_t gfn, union asce asce);
519 
520 long _dat_walk_gfn_range(gfn_t start, gfn_t end, union asce asce,
521 			 const struct dat_walk_ops *ops, int flags, void *priv);
522 
523 int dat_entry_walk(struct kvm_s390_mmu_cache *mc, gfn_t gfn, union asce asce, int flags,
524 		   int walk_level, union crste **last, union pte **ptepp);
525 void dat_free_level(struct crst_table *table, bool owns_ptes);
526 struct crst_table *dat_alloc_crst_sleepable(unsigned long init);
527 int dat_set_asce_limit(struct kvm_s390_mmu_cache *mc, union asce *asce, int newtype);
528 int dat_get_storage_key(union asce asce, gfn_t gfn, union skey *skey);
529 int dat_set_storage_key(struct kvm_s390_mmu_cache *mc, union asce asce, gfn_t gfn,
530 			union skey skey, bool nq);
531 int dat_cond_set_storage_key(struct kvm_s390_mmu_cache *mmc, union asce asce, gfn_t gfn,
532 			     union skey skey, union skey *oldkey, bool nq, bool mr, bool mc);
533 int dat_reset_reference_bit(union asce asce, gfn_t gfn);
534 long dat_reset_skeys(union asce asce, gfn_t start);
535 
536 unsigned long dat_get_ptval(struct page_table *table, struct ptval_param param);
537 void dat_set_ptval(struct page_table *table, struct ptval_param param, unsigned long val);
538 
539 int dat_set_slot(struct kvm_s390_mmu_cache *mc, union asce asce, gfn_t start, gfn_t end,
540 		 u16 type, u16 param);
541 int dat_set_prefix_notif_bit(union asce asce, gfn_t gfn);
542 bool dat_test_age_gfn(union asce asce, gfn_t start, gfn_t end);
543 int dat_link(struct kvm_s390_mmu_cache *mc, union asce asce, int level,
544 	     bool uses_skeys, struct guest_fault *f);
545 
546 int dat_perform_essa(union asce asce, gfn_t gfn, int orc, union essa_state *state, bool *dirty);
547 long dat_reset_cmma(union asce asce, gfn_t start_gfn);
548 int dat_peek_cmma(gfn_t start, union asce asce, unsigned int *count, u8 *values);
549 int dat_get_cmma(union asce asce, gfn_t *start, unsigned int *count, u8 *values, atomic64_t *rem);
550 int dat_set_cmma_bits(struct kvm_s390_mmu_cache *mc, union asce asce, gfn_t gfn,
551 		      unsigned long count, unsigned long mask, const uint8_t *bits);
552 
553 int kvm_s390_mmu_cache_topup(struct kvm_s390_mmu_cache *mc);
554 
555 #define GFP_KVM_S390_MMU_CACHE (GFP_ATOMIC | __GFP_ACCOUNT | __GFP_NOWARN)
556 
kvm_s390_mmu_cache_alloc_pt(struct kvm_s390_mmu_cache * mc)557 static inline struct page_table *kvm_s390_mmu_cache_alloc_pt(struct kvm_s390_mmu_cache *mc)
558 {
559 	if (mc->n_pts)
560 		return mc->pts[--mc->n_pts];
561 	return (void *)__get_free_page(GFP_KVM_S390_MMU_CACHE);
562 }
563 
kvm_s390_mmu_cache_alloc_crst(struct kvm_s390_mmu_cache * mc)564 static inline struct crst_table *kvm_s390_mmu_cache_alloc_crst(struct kvm_s390_mmu_cache *mc)
565 {
566 	if (mc->n_crsts)
567 		return mc->crsts[--mc->n_crsts];
568 	return (void *)__get_free_pages(GFP_KVM_S390_MMU_CACHE | __GFP_COMP, CRST_ALLOC_ORDER);
569 }
570 
kvm_s390_mmu_cache_alloc_rmap(struct kvm_s390_mmu_cache * mc)571 static inline struct vsie_rmap *kvm_s390_mmu_cache_alloc_rmap(struct kvm_s390_mmu_cache *mc)
572 {
573 	if (mc->n_rmaps)
574 		return mc->rmaps[--mc->n_rmaps];
575 	return kzalloc_obj(struct vsie_rmap, GFP_KVM_S390_MMU_CACHE);
576 }
577 
crste_table_start(union crste * crstep)578 static inline struct crst_table *crste_table_start(union crste *crstep)
579 {
580 	return (struct crst_table *)ALIGN_DOWN((unsigned long)crstep, _CRST_TABLE_SIZE);
581 }
582 
pte_table_start(union pte * ptep)583 static inline struct page_table *pte_table_start(union pte *ptep)
584 {
585 	return (struct page_table *)ALIGN_DOWN((unsigned long)ptep, _PAGE_TABLE_SIZE);
586 }
587 
crdte_crste(union crste * crstep,union crste old,union crste new,gfn_t gfn,union asce asce)588 static inline bool crdte_crste(union crste *crstep, union crste old, union crste new, gfn_t gfn,
589 			       union asce asce)
590 {
591 	unsigned long dtt = 0x10 | new.h.tt << 2;
592 	void *table = crste_table_start(crstep);
593 
594 	return crdte(old.val, new.val, table, dtt, gfn_to_gpa(gfn), asce.val);
595 }
596 
597 /**
598  * idte_crste() - invalidate a crste entry using idte
599  * @crstep: pointer to the crste to be invalidated
600  * @gfn: a gfn mapped by the crste
601  * @opt: options for the idte instruction
602  * @asce: the asce
603  * @local: whether the operation is cpu-local
604  */
idte_crste(union crste * crstep,gfn_t gfn,unsigned long opt,union asce asce,int local)605 static __always_inline void idte_crste(union crste *crstep, gfn_t gfn, unsigned long opt,
606 				       union asce asce, int local)
607 {
608 	unsigned long table_origin = __pa(crste_table_start(crstep));
609 	unsigned long gaddr = gfn_to_gpa(gfn) & HPAGE_MASK;
610 
611 	if (__builtin_constant_p(opt) && opt == 0) {
612 		/* flush without guest asce */
613 		asm volatile("idte	%[table_origin],0,%[gaddr],%[local]"
614 			: "+m" (*crstep)
615 			: [table_origin] "a" (table_origin), [gaddr] "a" (gaddr),
616 			  [local] "i" (local)
617 			: "cc");
618 	} else {
619 		/* flush with guest asce */
620 		asm volatile("idte %[table_origin],%[asce],%[gaddr_opt],%[local]"
621 			: "+m" (*crstep)
622 			: [table_origin] "a" (table_origin), [gaddr_opt] "a" (gaddr | opt),
623 			  [asce] "a" (asce.val), [local] "i" (local)
624 			: "cc");
625 	}
626 }
627 
dat_init_pgstes(struct page_table * pt,unsigned long val)628 static inline void dat_init_pgstes(struct page_table *pt, unsigned long val)
629 {
630 	memset64((void *)pt->pgstes, val, PTRS_PER_PTE);
631 }
632 
dat_init_page_table(struct page_table * pt,unsigned long ptes,unsigned long pgstes)633 static inline void dat_init_page_table(struct page_table *pt, unsigned long ptes,
634 				       unsigned long pgstes)
635 {
636 	memset64((void *)pt->ptes, ptes, PTRS_PER_PTE);
637 	dat_init_pgstes(pt, pgstes);
638 }
639 
asce_end(union asce asce)640 static inline gfn_t asce_end(union asce asce)
641 {
642 	return 1ULL << ((asce.dt + 1) * 11 + _SEGMENT_SHIFT - PAGE_SHIFT);
643 }
644 
645 #define _CRSTE(x) ((union crste) { .val = _Generic((x),	\
646 			union pgd : (x).val,		\
647 			union p4d : (x).val,		\
648 			union pud : (x).val,		\
649 			union pmd : (x).val,		\
650 			union crste : (x).val)})
651 
652 #define _CRSTEP(x) ((union crste *)_Generic((*(x)),	\
653 				union pgd : (x),	\
654 				union p4d : (x),	\
655 				union pud : (x),	\
656 				union pmd : (x),	\
657 				union crste : (x)))
658 
659 #define _CRSTP(x) ((struct crst_table *)_Generic((*(x)),	\
660 		struct crst_table : (x),			\
661 		struct segment_table : (x),			\
662 		struct region3_table : (x),			\
663 		struct region2_table : (x),			\
664 		struct region1_table : (x)))
665 
asce_contains_gfn(union asce asce,gfn_t gfn)666 static inline bool asce_contains_gfn(union asce asce, gfn_t gfn)
667 {
668 	return gfn < asce_end(asce);
669 }
670 
is_pmd(union crste crste)671 static inline bool is_pmd(union crste crste)
672 {
673 	return crste.h.tt == TABLE_TYPE_SEGMENT;
674 }
675 
is_pud(union crste crste)676 static inline bool is_pud(union crste crste)
677 {
678 	return crste.h.tt == TABLE_TYPE_REGION3;
679 }
680 
is_p4d(union crste crste)681 static inline bool is_p4d(union crste crste)
682 {
683 	return crste.h.tt == TABLE_TYPE_REGION2;
684 }
685 
is_pgd(union crste crste)686 static inline bool is_pgd(union crste crste)
687 {
688 	return crste.h.tt == TABLE_TYPE_REGION1;
689 }
690 
pmd_origin_large(union pmd pmd)691 static inline phys_addr_t pmd_origin_large(union pmd pmd)
692 {
693 	return pmd.val & _SEGMENT_ENTRY_ORIGIN_LARGE;
694 }
695 
pud_origin_large(union pud pud)696 static inline phys_addr_t pud_origin_large(union pud pud)
697 {
698 	return pud.val & _REGION3_ENTRY_ORIGIN_LARGE;
699 }
700 
701 /**
702  * crste_origin_large() - Return the large frame origin of a large crste
703  * @crste: The crste whose origin is to be returned. Should be either a
704  *         region-3 table entry or a segment table entry, in both cases with
705  *         FC set to 1 (large pages).
706  *
707  * Return: The origin of the large frame pointed to by @crste, or -1 if the
708  *         crste was not large (wrong table type, or FC==0)
709  */
crste_origin_large(union crste crste)710 static inline phys_addr_t crste_origin_large(union crste crste)
711 {
712 	if (unlikely(!crste.h.fc || crste.h.tt > TABLE_TYPE_REGION3))
713 		return -1;
714 	if (is_pmd(crste))
715 		return pmd_origin_large(crste.pmd);
716 	return pud_origin_large(crste.pud);
717 }
718 
719 #define crste_origin(x) (_Generic((x),				\
720 		union pmd : (x).val & _SEGMENT_ENTRY_ORIGIN,	\
721 		union pud : (x).val & _REGION_ENTRY_ORIGIN,	\
722 		union p4d : (x).val & _REGION_ENTRY_ORIGIN,	\
723 		union pgd : (x).val & _REGION_ENTRY_ORIGIN))
724 
pte_origin(union pte pte)725 static inline unsigned long pte_origin(union pte pte)
726 {
727 	return pte.val & PAGE_MASK;
728 }
729 
pmd_prefix(union pmd pmd)730 static inline bool pmd_prefix(union pmd pmd)
731 {
732 	return pmd.h.fc && pmd.s.fc1.prefix_notif;
733 }
734 
pud_prefix(union pud pud)735 static inline bool pud_prefix(union pud pud)
736 {
737 	return pud.h.fc && pud.s.fc1.prefix_notif;
738 }
739 
crste_leaf(union crste crste)740 static inline bool crste_leaf(union crste crste)
741 {
742 	return (crste.h.tt <= TABLE_TYPE_REGION3) && crste.h.fc;
743 }
744 
crste_prefix(union crste crste)745 static inline bool crste_prefix(union crste crste)
746 {
747 	return crste_leaf(crste) && crste.s.fc1.prefix_notif;
748 }
749 
crste_dirty(union crste crste)750 static inline bool crste_dirty(union crste crste)
751 {
752 	return crste_leaf(crste) && crste.s.fc1.d;
753 }
754 
pgste_of(union pte * pte)755 static inline union pgste *pgste_of(union pte *pte)
756 {
757 	return (union pgste *)(pte + _PAGE_ENTRIES);
758 }
759 
pte_hole(union pte pte)760 static inline bool pte_hole(union pte pte)
761 {
762 	return pte.h.i && !pte.tok.pr && pte.tok.type != _DAT_TOKEN_NONE;
763 }
764 
_crste_hole(union crste crste)765 static inline bool _crste_hole(union crste crste)
766 {
767 	return crste.h.i && !crste.tok.pr && crste.tok.type != _DAT_TOKEN_NONE;
768 }
769 
770 #define crste_hole(x) _crste_hole(_CRSTE(x))
771 
_crste_none(union crste crste)772 static inline bool _crste_none(union crste crste)
773 {
774 	return crste.h.i && !crste.tok.pr && crste.tok.type == _DAT_TOKEN_NONE;
775 }
776 
777 #define crste_none(x) _crste_none(_CRSTE(x))
778 
large_pud_to_phys(union pud pud,gfn_t gfn)779 static inline phys_addr_t large_pud_to_phys(union pud pud, gfn_t gfn)
780 {
781 	return pud_origin_large(pud) | (gfn_to_gpa(gfn) & ~_REGION3_MASK);
782 }
783 
large_pmd_to_phys(union pmd pmd,gfn_t gfn)784 static inline phys_addr_t large_pmd_to_phys(union pmd pmd, gfn_t gfn)
785 {
786 	return pmd_origin_large(pmd) | (gfn_to_gpa(gfn) & ~_SEGMENT_MASK);
787 }
788 
large_crste_to_phys(union crste crste,gfn_t gfn)789 static inline phys_addr_t large_crste_to_phys(union crste crste, gfn_t gfn)
790 {
791 	if (unlikely(!crste.h.fc || crste.h.tt > TABLE_TYPE_REGION3))
792 		return -1;
793 	if (is_pmd(crste))
794 		return large_pmd_to_phys(crste.pmd, gfn);
795 	return large_pud_to_phys(crste.pud, gfn);
796 }
797 
cspg_crste(union crste * crstep,union crste old,union crste new)798 static inline bool cspg_crste(union crste *crstep, union crste old, union crste new)
799 {
800 	return cspg(&crstep->val, old.val, new.val);
801 }
802 
dereference_pmd(union pmd pmd)803 static inline struct page_table *dereference_pmd(union pmd pmd)
804 {
805 	return phys_to_virt(crste_origin(pmd));
806 }
807 
dereference_pud(union pud pud)808 static inline struct segment_table *dereference_pud(union pud pud)
809 {
810 	return phys_to_virt(crste_origin(pud));
811 }
812 
dereference_p4d(union p4d p4d)813 static inline struct region3_table *dereference_p4d(union p4d p4d)
814 {
815 	return phys_to_virt(crste_origin(p4d));
816 }
817 
dereference_pgd(union pgd pgd)818 static inline struct region2_table *dereference_pgd(union pgd pgd)
819 {
820 	return phys_to_virt(crste_origin(pgd));
821 }
822 
_dereference_crste(union crste crste)823 static inline struct crst_table *_dereference_crste(union crste crste)
824 {
825 	if (unlikely(is_pmd(crste)))
826 		return NULL;
827 	return phys_to_virt(crste_origin(crste.pud));
828 }
829 
830 #define dereference_crste(x) (_Generic((x),			\
831 		union pud : _dereference_crste(_CRSTE(x)),	\
832 		union p4d : _dereference_crste(_CRSTE(x)),	\
833 		union pgd : _dereference_crste(_CRSTE(x)),	\
834 		union crste : _dereference_crste(_CRSTE(x))))
835 
dereference_asce(union asce asce)836 static inline struct crst_table *dereference_asce(union asce asce)
837 {
838 	return phys_to_virt(asce.val & _ASCE_ORIGIN);
839 }
840 
asce_flush_tlb(union asce asce)841 static inline void asce_flush_tlb(union asce asce)
842 {
843 	__tlb_flush_idte(asce.val);
844 }
845 
pgste_get_trylock(union pte * ptep,union pgste * res)846 static inline bool pgste_get_trylock(union pte *ptep, union pgste *res)
847 {
848 	union pgste *pgstep = pgste_of(ptep);
849 	union pgste old_pgste;
850 
851 	if (READ_ONCE(pgstep->val) & PGSTE_PCL_BIT)
852 		return false;
853 	old_pgste.val = __atomic64_or_barrier(PGSTE_PCL_BIT, &pgstep->val);
854 	if (old_pgste.pcl)
855 		return false;
856 	old_pgste.pcl = 1;
857 	*res = old_pgste;
858 	return true;
859 }
860 
pgste_get_lock(union pte * ptep)861 static inline union pgste pgste_get_lock(union pte *ptep)
862 {
863 	union pgste res;
864 
865 	while (!pgste_get_trylock(ptep, &res))
866 		cpu_relax();
867 	return res;
868 }
869 
pgste_set_unlock(union pte * ptep,union pgste pgste)870 static inline void pgste_set_unlock(union pte *ptep, union pgste pgste)
871 {
872 	pgste.pcl = 0;
873 	barrier();
874 	WRITE_ONCE(*pgste_of(ptep), pgste);
875 }
876 
dat_ptep_xchg(union pte * ptep,union pte new,gfn_t gfn,union asce asce,bool has_skeys)877 static inline void dat_ptep_xchg(union pte *ptep, union pte new, gfn_t gfn, union asce asce,
878 				 bool has_skeys)
879 {
880 	union pgste pgste;
881 
882 	pgste = pgste_get_lock(ptep);
883 	pgste = __dat_ptep_xchg(ptep, pgste, new, gfn, asce, has_skeys);
884 	pgste_set_unlock(ptep, pgste);
885 }
886 
dat_ptep_clear(union pte * ptep,gfn_t gfn,union asce asce,bool has_skeys)887 static inline void dat_ptep_clear(union pte *ptep, gfn_t gfn, union asce asce, bool has_skeys)
888 {
889 	dat_ptep_xchg(ptep, _PTE_EMPTY, gfn, asce, has_skeys);
890 }
891 
dat_free_pt(struct page_table * pt)892 static inline void dat_free_pt(struct page_table *pt)
893 {
894 	free_page((unsigned long)pt);
895 }
896 
_dat_free_crst(struct crst_table * table)897 static inline void _dat_free_crst(struct crst_table *table)
898 {
899 	free_pages((unsigned long)table, CRST_ALLOC_ORDER);
900 }
901 
902 #define dat_free_crst(x) _dat_free_crst(_CRSTP(x))
903 
kvm_s390_free_mmu_cache(struct kvm_s390_mmu_cache * mc)904 static inline void kvm_s390_free_mmu_cache(struct kvm_s390_mmu_cache *mc)
905 {
906 	if (!mc)
907 		return;
908 	while (mc->n_pts)
909 		dat_free_pt(mc->pts[--mc->n_pts]);
910 	while (mc->n_crsts)
911 		_dat_free_crst(mc->crsts[--mc->n_crsts]);
912 	while (mc->n_rmaps)
913 		kfree(mc->rmaps[--mc->n_rmaps]);
914 	kfree(mc);
915 }
916 
DEFINE_FREE(kvm_s390_mmu_cache,struct kvm_s390_mmu_cache *,if (_T)kvm_s390_free_mmu_cache (_T))917 DEFINE_FREE(kvm_s390_mmu_cache, struct kvm_s390_mmu_cache *, if (_T) kvm_s390_free_mmu_cache(_T))
918 
919 static inline struct kvm_s390_mmu_cache *kvm_s390_new_mmu_cache(void)
920 {
921 	struct kvm_s390_mmu_cache *mc __free(kvm_s390_mmu_cache) = NULL;
922 
923 	mc = kzalloc_obj(*mc, GFP_KERNEL_ACCOUNT);
924 	if (mc && !kvm_s390_mmu_cache_topup(mc))
925 		return_ptr(mc);
926 	return NULL;
927 }
928 
dat_pmdp_xchg_atomic(union pmd * pmdp,union pmd old,union pmd new,gfn_t gfn,union asce asce)929 static inline bool dat_pmdp_xchg_atomic(union pmd *pmdp, union pmd old, union pmd new,
930 					gfn_t gfn, union asce asce)
931 {
932 	return dat_crstep_xchg_atomic(_CRSTEP(pmdp), _CRSTE(old), _CRSTE(new), gfn, asce);
933 }
934 
dat_pudp_xchg_atomic(union pud * pudp,union pud old,union pud new,gfn_t gfn,union asce asce)935 static inline bool dat_pudp_xchg_atomic(union pud *pudp, union pud old, union pud new,
936 					gfn_t gfn, union asce asce)
937 {
938 	return dat_crstep_xchg_atomic(_CRSTEP(pudp), _CRSTE(old), _CRSTE(new), gfn, asce);
939 }
940 
dat_crstep_clear(union crste * crstep,gfn_t gfn,union asce asce)941 static inline void dat_crstep_clear(union crste *crstep, gfn_t gfn, union asce asce)
942 {
943 	union crste newcrste = _CRSTE_EMPTY(crstep->h.tt);
944 
945 	dat_crstep_xchg(crstep, newcrste, gfn, asce);
946 }
947 
get_level(union crste * crstep,union pte * ptep)948 static inline int get_level(union crste *crstep, union pte *ptep)
949 {
950 	return ptep ? TABLE_TYPE_PAGE_TABLE : crstep->h.tt;
951 }
952 
dat_delete_slot(struct kvm_s390_mmu_cache * mc,union asce asce,gfn_t start,unsigned long npages)953 static inline int dat_delete_slot(struct kvm_s390_mmu_cache *mc, union asce asce, gfn_t start,
954 				  unsigned long npages)
955 {
956 	return dat_set_slot(mc, asce, start, start + npages, _DAT_TOKEN_PIC, PGM_ADDRESSING);
957 }
958 
dat_create_slot(struct kvm_s390_mmu_cache * mc,union asce asce,gfn_t start,unsigned long npages)959 static inline int dat_create_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_NONE, 0);
963 }
964 
crste_is_ucas(union crste crste)965 static inline bool crste_is_ucas(union crste crste)
966 {
967 	return is_pmd(crste) && crste.h.i && crste.h.fc0.tl == 1 && crste.h.fc == 0;
968 }
969 
970 #endif /* __KVM_S390_DAT_H */
971