xref: /openbmc/linux/arch/s390/include/asm/pgtable.h (revision 77a87824)
1 /*
2  *  S390 version
3  *    Copyright IBM Corp. 1999, 2000
4  *    Author(s): Hartmut Penner (hp@de.ibm.com)
5  *               Ulrich Weigand (weigand@de.ibm.com)
6  *               Martin Schwidefsky (schwidefsky@de.ibm.com)
7  *
8  *  Derived from "include/asm-i386/pgtable.h"
9  */
10 
11 #ifndef _ASM_S390_PGTABLE_H
12 #define _ASM_S390_PGTABLE_H
13 
14 /*
15  * The Linux memory management assumes a three-level page table setup.
16  * For s390 64 bit we use up to four of the five levels the hardware
17  * provides (region first tables are not used).
18  *
19  * The "pgd_xxx()" functions are trivial for a folded two-level
20  * setup: the pgd is never bad, and a pmd always exists (as it's folded
21  * into the pgd entry)
22  *
23  * This file contains the functions and defines necessary to modify and use
24  * the S390 page table tree.
25  */
26 #ifndef __ASSEMBLY__
27 #include <linux/sched.h>
28 #include <linux/mm_types.h>
29 #include <linux/page-flags.h>
30 #include <linux/radix-tree.h>
31 #include <linux/atomic.h>
32 #include <asm/bug.h>
33 #include <asm/page.h>
34 
35 extern pgd_t swapper_pg_dir[];
36 extern void paging_init(void);
37 extern void vmem_map_init(void);
38 pmd_t *vmem_pmd_alloc(void);
39 pte_t *vmem_pte_alloc(void);
40 
41 enum {
42 	PG_DIRECT_MAP_4K = 0,
43 	PG_DIRECT_MAP_1M,
44 	PG_DIRECT_MAP_2G,
45 	PG_DIRECT_MAP_MAX
46 };
47 
48 extern atomic_long_t direct_pages_count[PG_DIRECT_MAP_MAX];
49 
50 static inline void update_page_count(int level, long count)
51 {
52 	if (IS_ENABLED(CONFIG_PROC_FS))
53 		atomic_long_add(count, &direct_pages_count[level]);
54 }
55 
56 struct seq_file;
57 void arch_report_meminfo(struct seq_file *m);
58 
59 /*
60  * The S390 doesn't have any external MMU info: the kernel page
61  * tables contain all the necessary information.
62  */
63 #define update_mmu_cache(vma, address, ptep)     do { } while (0)
64 #define update_mmu_cache_pmd(vma, address, ptep) do { } while (0)
65 
66 /*
67  * ZERO_PAGE is a global shared page that is always zero; used
68  * for zero-mapped memory areas etc..
69  */
70 
71 extern unsigned long empty_zero_page;
72 extern unsigned long zero_page_mask;
73 
74 #define ZERO_PAGE(vaddr) \
75 	(virt_to_page((void *)(empty_zero_page + \
76 	 (((unsigned long)(vaddr)) &zero_page_mask))))
77 #define __HAVE_COLOR_ZERO_PAGE
78 
79 /* TODO: s390 cannot support io_remap_pfn_range... */
80 #endif /* !__ASSEMBLY__ */
81 
82 /*
83  * PMD_SHIFT determines the size of the area a second-level page
84  * table can map
85  * PGDIR_SHIFT determines what a third-level page table entry can map
86  */
87 #define PMD_SHIFT	20
88 #define PUD_SHIFT	31
89 #define PGDIR_SHIFT	42
90 
91 #define PMD_SIZE        (1UL << PMD_SHIFT)
92 #define PMD_MASK        (~(PMD_SIZE-1))
93 #define PUD_SIZE	(1UL << PUD_SHIFT)
94 #define PUD_MASK	(~(PUD_SIZE-1))
95 #define PGDIR_SIZE	(1UL << PGDIR_SHIFT)
96 #define PGDIR_MASK	(~(PGDIR_SIZE-1))
97 
98 /*
99  * entries per page directory level: the S390 is two-level, so
100  * we don't really have any PMD directory physically.
101  * for S390 segment-table entries are combined to one PGD
102  * that leads to 1024 pte per pgd
103  */
104 #define PTRS_PER_PTE	256
105 #define PTRS_PER_PMD	2048
106 #define PTRS_PER_PUD	2048
107 #define PTRS_PER_PGD	2048
108 
109 #define FIRST_USER_ADDRESS  0UL
110 
111 #define pte_ERROR(e) \
112 	printk("%s:%d: bad pte %p.\n", __FILE__, __LINE__, (void *) pte_val(e))
113 #define pmd_ERROR(e) \
114 	printk("%s:%d: bad pmd %p.\n", __FILE__, __LINE__, (void *) pmd_val(e))
115 #define pud_ERROR(e) \
116 	printk("%s:%d: bad pud %p.\n", __FILE__, __LINE__, (void *) pud_val(e))
117 #define pgd_ERROR(e) \
118 	printk("%s:%d: bad pgd %p.\n", __FILE__, __LINE__, (void *) pgd_val(e))
119 
120 #ifndef __ASSEMBLY__
121 /*
122  * The vmalloc and module area will always be on the topmost area of the
123  * kernel mapping. We reserve 128GB (64bit) for vmalloc and modules.
124  * On 64 bit kernels we have a 2GB area at the top of the vmalloc area where
125  * modules will reside. That makes sure that inter module branches always
126  * happen without trampolines and in addition the placement within a 2GB frame
127  * is branch prediction unit friendly.
128  */
129 extern unsigned long VMALLOC_START;
130 extern unsigned long VMALLOC_END;
131 extern struct page *vmemmap;
132 
133 #define VMEM_MAX_PHYS ((unsigned long) vmemmap)
134 
135 extern unsigned long MODULES_VADDR;
136 extern unsigned long MODULES_END;
137 #define MODULES_VADDR	MODULES_VADDR
138 #define MODULES_END	MODULES_END
139 #define MODULES_LEN	(1UL << 31)
140 
141 static inline int is_module_addr(void *addr)
142 {
143 	BUILD_BUG_ON(MODULES_LEN > (1UL << 31));
144 	if (addr < (void *)MODULES_VADDR)
145 		return 0;
146 	if (addr > (void *)MODULES_END)
147 		return 0;
148 	return 1;
149 }
150 
151 /*
152  * A 64 bit pagetable entry of S390 has following format:
153  * |			 PFRA			      |0IPC|  OS  |
154  * 0000000000111111111122222222223333333333444444444455555555556666
155  * 0123456789012345678901234567890123456789012345678901234567890123
156  *
157  * I Page-Invalid Bit:    Page is not available for address-translation
158  * P Page-Protection Bit: Store access not possible for page
159  * C Change-bit override: HW is not required to set change bit
160  *
161  * A 64 bit segmenttable entry of S390 has following format:
162  * |        P-table origin                              |      TT
163  * 0000000000111111111122222222223333333333444444444455555555556666
164  * 0123456789012345678901234567890123456789012345678901234567890123
165  *
166  * I Segment-Invalid Bit:    Segment is not available for address-translation
167  * C Common-Segment Bit:     Segment is not private (PoP 3-30)
168  * P Page-Protection Bit: Store access not possible for page
169  * TT Type 00
170  *
171  * A 64 bit region table entry of S390 has following format:
172  * |        S-table origin                             |   TF  TTTL
173  * 0000000000111111111122222222223333333333444444444455555555556666
174  * 0123456789012345678901234567890123456789012345678901234567890123
175  *
176  * I Segment-Invalid Bit:    Segment is not available for address-translation
177  * TT Type 01
178  * TF
179  * TL Table length
180  *
181  * The 64 bit regiontable origin of S390 has following format:
182  * |      region table origon                          |       DTTL
183  * 0000000000111111111122222222223333333333444444444455555555556666
184  * 0123456789012345678901234567890123456789012345678901234567890123
185  *
186  * X Space-Switch event:
187  * G Segment-Invalid Bit:
188  * P Private-Space Bit:
189  * S Storage-Alteration:
190  * R Real space
191  * TL Table-Length:
192  *
193  * A storage key has the following format:
194  * | ACC |F|R|C|0|
195  *  0   3 4 5 6 7
196  * ACC: access key
197  * F  : fetch protection bit
198  * R  : referenced bit
199  * C  : changed bit
200  */
201 
202 /* Hardware bits in the page table entry */
203 #define _PAGE_PROTECT	0x200		/* HW read-only bit  */
204 #define _PAGE_INVALID	0x400		/* HW invalid bit    */
205 #define _PAGE_LARGE	0x800		/* Bit to mark a large pte */
206 
207 /* Software bits in the page table entry */
208 #define _PAGE_PRESENT	0x001		/* SW pte present bit */
209 #define _PAGE_YOUNG	0x004		/* SW pte young bit */
210 #define _PAGE_DIRTY	0x008		/* SW pte dirty bit */
211 #define _PAGE_READ	0x010		/* SW pte read bit */
212 #define _PAGE_WRITE	0x020		/* SW pte write bit */
213 #define _PAGE_SPECIAL	0x040		/* SW associated with special page */
214 #define _PAGE_UNUSED	0x080		/* SW bit for pgste usage state */
215 #define __HAVE_ARCH_PTE_SPECIAL
216 
217 #ifdef CONFIG_MEM_SOFT_DIRTY
218 #define _PAGE_SOFT_DIRTY 0x002		/* SW pte soft dirty bit */
219 #else
220 #define _PAGE_SOFT_DIRTY 0x000
221 #endif
222 
223 /* Set of bits not changed in pte_modify */
224 #define _PAGE_CHG_MASK		(PAGE_MASK | _PAGE_SPECIAL | _PAGE_DIRTY | \
225 				 _PAGE_YOUNG | _PAGE_SOFT_DIRTY)
226 
227 /*
228  * handle_pte_fault uses pte_present and pte_none to find out the pte type
229  * WITHOUT holding the page table lock. The _PAGE_PRESENT bit is used to
230  * distinguish present from not-present ptes. It is changed only with the page
231  * table lock held.
232  *
233  * The following table gives the different possible bit combinations for
234  * the pte hardware and software bits in the last 12 bits of a pte
235  * (. unassigned bit, x don't care, t swap type):
236  *
237  *				842100000000
238  *				000084210000
239  *				000000008421
240  *				.IR.uswrdy.p
241  * empty			.10.00000000
242  * swap				.11..ttttt.0
243  * prot-none, clean, old	.11.xx0000.1
244  * prot-none, clean, young	.11.xx0001.1
245  * prot-none, dirty, old	.10.xx0010.1
246  * prot-none, dirty, young	.10.xx0011.1
247  * read-only, clean, old	.11.xx0100.1
248  * read-only, clean, young	.01.xx0101.1
249  * read-only, dirty, old	.11.xx0110.1
250  * read-only, dirty, young	.01.xx0111.1
251  * read-write, clean, old	.11.xx1100.1
252  * read-write, clean, young	.01.xx1101.1
253  * read-write, dirty, old	.10.xx1110.1
254  * read-write, dirty, young	.00.xx1111.1
255  * HW-bits: R read-only, I invalid
256  * SW-bits: p present, y young, d dirty, r read, w write, s special,
257  *	    u unused, l large
258  *
259  * pte_none    is true for the bit pattern .10.00000000, pte == 0x400
260  * pte_swap    is true for the bit pattern .11..ooooo.0, (pte & 0x201) == 0x200
261  * pte_present is true for the bit pattern .xx.xxxxxx.1, (pte & 0x001) == 0x001
262  */
263 
264 /* Bits in the segment/region table address-space-control-element */
265 #define _ASCE_ORIGIN		~0xfffUL/* segment table origin		    */
266 #define _ASCE_PRIVATE_SPACE	0x100	/* private space control	    */
267 #define _ASCE_ALT_EVENT		0x80	/* storage alteration event control */
268 #define _ASCE_SPACE_SWITCH	0x40	/* space switch event		    */
269 #define _ASCE_REAL_SPACE	0x20	/* real space control		    */
270 #define _ASCE_TYPE_MASK		0x0c	/* asce table type mask		    */
271 #define _ASCE_TYPE_REGION1	0x0c	/* region first table type	    */
272 #define _ASCE_TYPE_REGION2	0x08	/* region second table type	    */
273 #define _ASCE_TYPE_REGION3	0x04	/* region third table type	    */
274 #define _ASCE_TYPE_SEGMENT	0x00	/* segment table type		    */
275 #define _ASCE_TABLE_LENGTH	0x03	/* region table length		    */
276 
277 /* Bits in the region table entry */
278 #define _REGION_ENTRY_ORIGIN	~0xfffUL/* region/segment table origin	    */
279 #define _REGION_ENTRY_PROTECT	0x200	/* region protection bit	    */
280 #define _REGION_ENTRY_INVALID	0x20	/* invalid region table entry	    */
281 #define _REGION_ENTRY_TYPE_MASK	0x0c	/* region/segment table type mask   */
282 #define _REGION_ENTRY_TYPE_R1	0x0c	/* region first table type	    */
283 #define _REGION_ENTRY_TYPE_R2	0x08	/* region second table type	    */
284 #define _REGION_ENTRY_TYPE_R3	0x04	/* region third table type	    */
285 #define _REGION_ENTRY_LENGTH	0x03	/* region third length		    */
286 
287 #define _REGION1_ENTRY		(_REGION_ENTRY_TYPE_R1 | _REGION_ENTRY_LENGTH)
288 #define _REGION1_ENTRY_EMPTY	(_REGION_ENTRY_TYPE_R1 | _REGION_ENTRY_INVALID)
289 #define _REGION2_ENTRY		(_REGION_ENTRY_TYPE_R2 | _REGION_ENTRY_LENGTH)
290 #define _REGION2_ENTRY_EMPTY	(_REGION_ENTRY_TYPE_R2 | _REGION_ENTRY_INVALID)
291 #define _REGION3_ENTRY		(_REGION_ENTRY_TYPE_R3 | _REGION_ENTRY_LENGTH)
292 #define _REGION3_ENTRY_EMPTY	(_REGION_ENTRY_TYPE_R3 | _REGION_ENTRY_INVALID)
293 
294 #define _REGION3_ENTRY_ORIGIN_LARGE ~0x7fffffffUL /* large page address	     */
295 #define _REGION3_ENTRY_ORIGIN  ~0x7ffUL/* region third table origin	     */
296 
297 #define _REGION3_ENTRY_DIRTY	0x2000	/* SW region dirty bit */
298 #define _REGION3_ENTRY_YOUNG	0x1000	/* SW region young bit */
299 #define _REGION3_ENTRY_LARGE	0x0400	/* RTTE-format control, large page  */
300 #define _REGION3_ENTRY_READ	0x0002	/* SW region read bit */
301 #define _REGION3_ENTRY_WRITE	0x0001	/* SW region write bit */
302 
303 #ifdef CONFIG_MEM_SOFT_DIRTY
304 #define _REGION3_ENTRY_SOFT_DIRTY 0x4000 /* SW region soft dirty bit */
305 #else
306 #define _REGION3_ENTRY_SOFT_DIRTY 0x0000 /* SW region soft dirty bit */
307 #endif
308 
309 #define _REGION_ENTRY_BITS	 0xfffffffffffff227UL
310 #define _REGION_ENTRY_BITS_LARGE 0xffffffff8000fe27UL
311 
312 /* Bits in the segment table entry */
313 #define _SEGMENT_ENTRY_BITS	0xfffffffffffffe33UL
314 #define _SEGMENT_ENTRY_BITS_LARGE 0xfffffffffff0ff33UL
315 #define _SEGMENT_ENTRY_ORIGIN_LARGE ~0xfffffUL /* large page address	    */
316 #define _SEGMENT_ENTRY_ORIGIN	~0x7ffUL/* segment table origin		    */
317 #define _SEGMENT_ENTRY_PROTECT	0x200	/* page protection bit		    */
318 #define _SEGMENT_ENTRY_INVALID	0x20	/* invalid segment table entry	    */
319 
320 #define _SEGMENT_ENTRY		(0)
321 #define _SEGMENT_ENTRY_EMPTY	(_SEGMENT_ENTRY_INVALID)
322 
323 #define _SEGMENT_ENTRY_DIRTY	0x2000	/* SW segment dirty bit */
324 #define _SEGMENT_ENTRY_YOUNG	0x1000	/* SW segment young bit */
325 #define _SEGMENT_ENTRY_LARGE	0x0400	/* STE-format control, large page */
326 #define _SEGMENT_ENTRY_READ	0x0002	/* SW segment read bit */
327 #define _SEGMENT_ENTRY_WRITE	0x0001	/* SW segment write bit */
328 
329 #ifdef CONFIG_MEM_SOFT_DIRTY
330 #define _SEGMENT_ENTRY_SOFT_DIRTY 0x4000 /* SW segment soft dirty bit */
331 #else
332 #define _SEGMENT_ENTRY_SOFT_DIRTY 0x0000 /* SW segment soft dirty bit */
333 #endif
334 
335 /*
336  * Segment table and region3 table entry encoding
337  * (R = read-only, I = invalid, y = young bit):
338  *				dy..R...I...rw
339  * prot-none, clean, old	00..1...1...00
340  * prot-none, clean, young	01..1...1...00
341  * prot-none, dirty, old	10..1...1...00
342  * prot-none, dirty, young	11..1...1...00
343  * read-only, clean, old	00..1...1...10
344  * read-only, clean, young	01..1...0...10
345  * read-only, dirty, old	10..1...1...10
346  * read-only, dirty, young	11..1...0...10
347  * read-write, clean, old	00..1...1...11
348  * read-write, clean, young	01..1...0...11
349  * read-write, dirty, old	10..0...1...11
350  * read-write, dirty, young	11..0...0...11
351  * The segment table origin is used to distinguish empty (origin==0) from
352  * read-write, old segment table entries (origin!=0)
353  * HW-bits: R read-only, I invalid
354  * SW-bits: y young, d dirty, r read, w write
355  */
356 
357 /* Page status table bits for virtualization */
358 #define PGSTE_ACC_BITS	0xf000000000000000UL
359 #define PGSTE_FP_BIT	0x0800000000000000UL
360 #define PGSTE_PCL_BIT	0x0080000000000000UL
361 #define PGSTE_HR_BIT	0x0040000000000000UL
362 #define PGSTE_HC_BIT	0x0020000000000000UL
363 #define PGSTE_GR_BIT	0x0004000000000000UL
364 #define PGSTE_GC_BIT	0x0002000000000000UL
365 #define PGSTE_UC_BIT	0x0000800000000000UL	/* user dirty (migration) */
366 #define PGSTE_IN_BIT	0x0000400000000000UL	/* IPTE notify bit */
367 
368 /* Guest Page State used for virtualization */
369 #define _PGSTE_GPS_ZERO		0x0000000080000000UL
370 #define _PGSTE_GPS_USAGE_MASK	0x0000000003000000UL
371 #define _PGSTE_GPS_USAGE_STABLE 0x0000000000000000UL
372 #define _PGSTE_GPS_USAGE_UNUSED 0x0000000001000000UL
373 
374 /*
375  * A user page table pointer has the space-switch-event bit, the
376  * private-space-control bit and the storage-alteration-event-control
377  * bit set. A kernel page table pointer doesn't need them.
378  */
379 #define _ASCE_USER_BITS		(_ASCE_SPACE_SWITCH | _ASCE_PRIVATE_SPACE | \
380 				 _ASCE_ALT_EVENT)
381 
382 /*
383  * Page protection definitions.
384  */
385 #define PAGE_NONE	__pgprot(_PAGE_PRESENT | _PAGE_INVALID)
386 #define PAGE_READ	__pgprot(_PAGE_PRESENT | _PAGE_READ | \
387 				 _PAGE_INVALID | _PAGE_PROTECT)
388 #define PAGE_WRITE	__pgprot(_PAGE_PRESENT | _PAGE_READ | _PAGE_WRITE | \
389 				 _PAGE_INVALID | _PAGE_PROTECT)
390 
391 #define PAGE_SHARED	__pgprot(_PAGE_PRESENT | _PAGE_READ | _PAGE_WRITE | \
392 				 _PAGE_YOUNG | _PAGE_DIRTY)
393 #define PAGE_KERNEL	__pgprot(_PAGE_PRESENT | _PAGE_READ | _PAGE_WRITE | \
394 				 _PAGE_YOUNG | _PAGE_DIRTY)
395 #define PAGE_KERNEL_RO	__pgprot(_PAGE_PRESENT | _PAGE_READ | _PAGE_YOUNG | \
396 				 _PAGE_PROTECT)
397 
398 /*
399  * On s390 the page table entry has an invalid bit and a read-only bit.
400  * Read permission implies execute permission and write permission
401  * implies read permission.
402  */
403          /*xwr*/
404 #define __P000	PAGE_NONE
405 #define __P001	PAGE_READ
406 #define __P010	PAGE_READ
407 #define __P011	PAGE_READ
408 #define __P100	PAGE_READ
409 #define __P101	PAGE_READ
410 #define __P110	PAGE_READ
411 #define __P111	PAGE_READ
412 
413 #define __S000	PAGE_NONE
414 #define __S001	PAGE_READ
415 #define __S010	PAGE_WRITE
416 #define __S011	PAGE_WRITE
417 #define __S100	PAGE_READ
418 #define __S101	PAGE_READ
419 #define __S110	PAGE_WRITE
420 #define __S111	PAGE_WRITE
421 
422 /*
423  * Segment entry (large page) protection definitions.
424  */
425 #define SEGMENT_NONE	__pgprot(_SEGMENT_ENTRY_INVALID | \
426 				 _SEGMENT_ENTRY_PROTECT)
427 #define SEGMENT_READ	__pgprot(_SEGMENT_ENTRY_PROTECT | \
428 				 _SEGMENT_ENTRY_READ)
429 #define SEGMENT_WRITE	__pgprot(_SEGMENT_ENTRY_READ | \
430 				 _SEGMENT_ENTRY_WRITE)
431 #define SEGMENT_KERNEL	__pgprot(_SEGMENT_ENTRY |	\
432 				 _SEGMENT_ENTRY_LARGE |	\
433 				 _SEGMENT_ENTRY_READ |	\
434 				 _SEGMENT_ENTRY_WRITE | \
435 				 _SEGMENT_ENTRY_YOUNG | \
436 				 _SEGMENT_ENTRY_DIRTY)
437 #define SEGMENT_KERNEL_RO __pgprot(_SEGMENT_ENTRY |	\
438 				 _SEGMENT_ENTRY_LARGE |	\
439 				 _SEGMENT_ENTRY_READ |	\
440 				 _SEGMENT_ENTRY_YOUNG |	\
441 				 _SEGMENT_ENTRY_PROTECT)
442 
443 /*
444  * Region3 entry (large page) protection definitions.
445  */
446 
447 #define REGION3_KERNEL	__pgprot(_REGION_ENTRY_TYPE_R3 | \
448 				 _REGION3_ENTRY_LARGE |	 \
449 				 _REGION3_ENTRY_READ |	 \
450 				 _REGION3_ENTRY_WRITE |	 \
451 				 _REGION3_ENTRY_YOUNG |	 \
452 				 _REGION3_ENTRY_DIRTY)
453 #define REGION3_KERNEL_RO __pgprot(_REGION_ENTRY_TYPE_R3 | \
454 				   _REGION3_ENTRY_LARGE |  \
455 				   _REGION3_ENTRY_READ |   \
456 				   _REGION3_ENTRY_YOUNG |  \
457 				   _REGION_ENTRY_PROTECT)
458 
459 static inline int mm_has_pgste(struct mm_struct *mm)
460 {
461 #ifdef CONFIG_PGSTE
462 	if (unlikely(mm->context.has_pgste))
463 		return 1;
464 #endif
465 	return 0;
466 }
467 
468 static inline int mm_alloc_pgste(struct mm_struct *mm)
469 {
470 #ifdef CONFIG_PGSTE
471 	if (unlikely(mm->context.alloc_pgste))
472 		return 1;
473 #endif
474 	return 0;
475 }
476 
477 /*
478  * In the case that a guest uses storage keys
479  * faults should no longer be backed by zero pages
480  */
481 #define mm_forbids_zeropage mm_use_skey
482 static inline int mm_use_skey(struct mm_struct *mm)
483 {
484 #ifdef CONFIG_PGSTE
485 	if (mm->context.use_skey)
486 		return 1;
487 #endif
488 	return 0;
489 }
490 
491 static inline void csp(unsigned int *ptr, unsigned int old, unsigned int new)
492 {
493 	register unsigned long reg2 asm("2") = old;
494 	register unsigned long reg3 asm("3") = new;
495 	unsigned long address = (unsigned long)ptr | 1;
496 
497 	asm volatile(
498 		"	csp	%0,%3"
499 		: "+d" (reg2), "+m" (*ptr)
500 		: "d" (reg3), "d" (address)
501 		: "cc");
502 }
503 
504 static inline void cspg(unsigned long *ptr, unsigned long old, unsigned long new)
505 {
506 	register unsigned long reg2 asm("2") = old;
507 	register unsigned long reg3 asm("3") = new;
508 	unsigned long address = (unsigned long)ptr | 1;
509 
510 	asm volatile(
511 		"	.insn	rre,0xb98a0000,%0,%3"
512 		: "+d" (reg2), "+m" (*ptr)
513 		: "d" (reg3), "d" (address)
514 		: "cc");
515 }
516 
517 #define CRDTE_DTT_PAGE		0x00UL
518 #define CRDTE_DTT_SEGMENT	0x10UL
519 #define CRDTE_DTT_REGION3	0x14UL
520 #define CRDTE_DTT_REGION2	0x18UL
521 #define CRDTE_DTT_REGION1	0x1cUL
522 
523 static inline void crdte(unsigned long old, unsigned long new,
524 			 unsigned long table, unsigned long dtt,
525 			 unsigned long address, unsigned long asce)
526 {
527 	register unsigned long reg2 asm("2") = old;
528 	register unsigned long reg3 asm("3") = new;
529 	register unsigned long reg4 asm("4") = table | dtt;
530 	register unsigned long reg5 asm("5") = address;
531 
532 	asm volatile(".insn rrf,0xb98f0000,%0,%2,%4,0"
533 		     : "+d" (reg2)
534 		     : "d" (reg3), "d" (reg4), "d" (reg5), "a" (asce)
535 		     : "memory", "cc");
536 }
537 
538 /*
539  * pgd/pmd/pte query functions
540  */
541 static inline int pgd_present(pgd_t pgd)
542 {
543 	if ((pgd_val(pgd) & _REGION_ENTRY_TYPE_MASK) < _REGION_ENTRY_TYPE_R2)
544 		return 1;
545 	return (pgd_val(pgd) & _REGION_ENTRY_ORIGIN) != 0UL;
546 }
547 
548 static inline int pgd_none(pgd_t pgd)
549 {
550 	if ((pgd_val(pgd) & _REGION_ENTRY_TYPE_MASK) < _REGION_ENTRY_TYPE_R2)
551 		return 0;
552 	return (pgd_val(pgd) & _REGION_ENTRY_INVALID) != 0UL;
553 }
554 
555 static inline int pgd_bad(pgd_t pgd)
556 {
557 	/*
558 	 * With dynamic page table levels the pgd can be a region table
559 	 * entry or a segment table entry. Check for the bit that are
560 	 * invalid for either table entry.
561 	 */
562 	unsigned long mask =
563 		~_SEGMENT_ENTRY_ORIGIN & ~_REGION_ENTRY_INVALID &
564 		~_REGION_ENTRY_TYPE_MASK & ~_REGION_ENTRY_LENGTH;
565 	return (pgd_val(pgd) & mask) != 0;
566 }
567 
568 static inline int pud_present(pud_t pud)
569 {
570 	if ((pud_val(pud) & _REGION_ENTRY_TYPE_MASK) < _REGION_ENTRY_TYPE_R3)
571 		return 1;
572 	return (pud_val(pud) & _REGION_ENTRY_ORIGIN) != 0UL;
573 }
574 
575 static inline int pud_none(pud_t pud)
576 {
577 	if ((pud_val(pud) & _REGION_ENTRY_TYPE_MASK) < _REGION_ENTRY_TYPE_R3)
578 		return 0;
579 	return pud_val(pud) == _REGION3_ENTRY_EMPTY;
580 }
581 
582 static inline int pud_large(pud_t pud)
583 {
584 	if ((pud_val(pud) & _REGION_ENTRY_TYPE_MASK) != _REGION_ENTRY_TYPE_R3)
585 		return 0;
586 	return !!(pud_val(pud) & _REGION3_ENTRY_LARGE);
587 }
588 
589 static inline unsigned long pud_pfn(pud_t pud)
590 {
591 	unsigned long origin_mask;
592 
593 	origin_mask = _REGION3_ENTRY_ORIGIN;
594 	if (pud_large(pud))
595 		origin_mask = _REGION3_ENTRY_ORIGIN_LARGE;
596 	return (pud_val(pud) & origin_mask) >> PAGE_SHIFT;
597 }
598 
599 static inline int pmd_large(pmd_t pmd)
600 {
601 	return (pmd_val(pmd) & _SEGMENT_ENTRY_LARGE) != 0;
602 }
603 
604 static inline int pmd_bad(pmd_t pmd)
605 {
606 	if (pmd_large(pmd))
607 		return (pmd_val(pmd) & ~_SEGMENT_ENTRY_BITS_LARGE) != 0;
608 	return (pmd_val(pmd) & ~_SEGMENT_ENTRY_BITS) != 0;
609 }
610 
611 static inline int pud_bad(pud_t pud)
612 {
613 	if ((pud_val(pud) & _REGION_ENTRY_TYPE_MASK) < _REGION_ENTRY_TYPE_R3)
614 		return pmd_bad(__pmd(pud_val(pud)));
615 	if (pud_large(pud))
616 		return (pud_val(pud) & ~_REGION_ENTRY_BITS_LARGE) != 0;
617 	return (pud_val(pud) & ~_REGION_ENTRY_BITS) != 0;
618 }
619 
620 static inline int pmd_present(pmd_t pmd)
621 {
622 	return pmd_val(pmd) != _SEGMENT_ENTRY_INVALID;
623 }
624 
625 static inline int pmd_none(pmd_t pmd)
626 {
627 	return pmd_val(pmd) == _SEGMENT_ENTRY_INVALID;
628 }
629 
630 static inline unsigned long pmd_pfn(pmd_t pmd)
631 {
632 	unsigned long origin_mask;
633 
634 	origin_mask = _SEGMENT_ENTRY_ORIGIN;
635 	if (pmd_large(pmd))
636 		origin_mask = _SEGMENT_ENTRY_ORIGIN_LARGE;
637 	return (pmd_val(pmd) & origin_mask) >> PAGE_SHIFT;
638 }
639 
640 #define __HAVE_ARCH_PMD_WRITE
641 static inline int pmd_write(pmd_t pmd)
642 {
643 	return (pmd_val(pmd) & _SEGMENT_ENTRY_WRITE) != 0;
644 }
645 
646 static inline int pmd_dirty(pmd_t pmd)
647 {
648 	int dirty = 1;
649 	if (pmd_large(pmd))
650 		dirty = (pmd_val(pmd) & _SEGMENT_ENTRY_DIRTY) != 0;
651 	return dirty;
652 }
653 
654 static inline int pmd_young(pmd_t pmd)
655 {
656 	int young = 1;
657 	if (pmd_large(pmd))
658 		young = (pmd_val(pmd) & _SEGMENT_ENTRY_YOUNG) != 0;
659 	return young;
660 }
661 
662 static inline int pte_present(pte_t pte)
663 {
664 	/* Bit pattern: (pte & 0x001) == 0x001 */
665 	return (pte_val(pte) & _PAGE_PRESENT) != 0;
666 }
667 
668 static inline int pte_none(pte_t pte)
669 {
670 	/* Bit pattern: pte == 0x400 */
671 	return pte_val(pte) == _PAGE_INVALID;
672 }
673 
674 static inline int pte_swap(pte_t pte)
675 {
676 	/* Bit pattern: (pte & 0x201) == 0x200 */
677 	return (pte_val(pte) & (_PAGE_PROTECT | _PAGE_PRESENT))
678 		== _PAGE_PROTECT;
679 }
680 
681 static inline int pte_special(pte_t pte)
682 {
683 	return (pte_val(pte) & _PAGE_SPECIAL);
684 }
685 
686 #define __HAVE_ARCH_PTE_SAME
687 static inline int pte_same(pte_t a, pte_t b)
688 {
689 	return pte_val(a) == pte_val(b);
690 }
691 
692 #ifdef CONFIG_NUMA_BALANCING
693 static inline int pte_protnone(pte_t pte)
694 {
695 	return pte_present(pte) && !(pte_val(pte) & _PAGE_READ);
696 }
697 
698 static inline int pmd_protnone(pmd_t pmd)
699 {
700 	/* pmd_large(pmd) implies pmd_present(pmd) */
701 	return pmd_large(pmd) && !(pmd_val(pmd) & _SEGMENT_ENTRY_READ);
702 }
703 #endif
704 
705 static inline int pte_soft_dirty(pte_t pte)
706 {
707 	return pte_val(pte) & _PAGE_SOFT_DIRTY;
708 }
709 #define pte_swp_soft_dirty pte_soft_dirty
710 
711 static inline pte_t pte_mksoft_dirty(pte_t pte)
712 {
713 	pte_val(pte) |= _PAGE_SOFT_DIRTY;
714 	return pte;
715 }
716 #define pte_swp_mksoft_dirty pte_mksoft_dirty
717 
718 static inline pte_t pte_clear_soft_dirty(pte_t pte)
719 {
720 	pte_val(pte) &= ~_PAGE_SOFT_DIRTY;
721 	return pte;
722 }
723 #define pte_swp_clear_soft_dirty pte_clear_soft_dirty
724 
725 static inline int pmd_soft_dirty(pmd_t pmd)
726 {
727 	return pmd_val(pmd) & _SEGMENT_ENTRY_SOFT_DIRTY;
728 }
729 
730 static inline pmd_t pmd_mksoft_dirty(pmd_t pmd)
731 {
732 	pmd_val(pmd) |= _SEGMENT_ENTRY_SOFT_DIRTY;
733 	return pmd;
734 }
735 
736 static inline pmd_t pmd_clear_soft_dirty(pmd_t pmd)
737 {
738 	pmd_val(pmd) &= ~_SEGMENT_ENTRY_SOFT_DIRTY;
739 	return pmd;
740 }
741 
742 /*
743  * query functions pte_write/pte_dirty/pte_young only work if
744  * pte_present() is true. Undefined behaviour if not..
745  */
746 static inline int pte_write(pte_t pte)
747 {
748 	return (pte_val(pte) & _PAGE_WRITE) != 0;
749 }
750 
751 static inline int pte_dirty(pte_t pte)
752 {
753 	return (pte_val(pte) & _PAGE_DIRTY) != 0;
754 }
755 
756 static inline int pte_young(pte_t pte)
757 {
758 	return (pte_val(pte) & _PAGE_YOUNG) != 0;
759 }
760 
761 #define __HAVE_ARCH_PTE_UNUSED
762 static inline int pte_unused(pte_t pte)
763 {
764 	return pte_val(pte) & _PAGE_UNUSED;
765 }
766 
767 /*
768  * pgd/pmd/pte modification functions
769  */
770 
771 static inline void pgd_clear(pgd_t *pgd)
772 {
773 	if ((pgd_val(*pgd) & _REGION_ENTRY_TYPE_MASK) == _REGION_ENTRY_TYPE_R2)
774 		pgd_val(*pgd) = _REGION2_ENTRY_EMPTY;
775 }
776 
777 static inline void pud_clear(pud_t *pud)
778 {
779 	if ((pud_val(*pud) & _REGION_ENTRY_TYPE_MASK) == _REGION_ENTRY_TYPE_R3)
780 		pud_val(*pud) = _REGION3_ENTRY_EMPTY;
781 }
782 
783 static inline void pmd_clear(pmd_t *pmdp)
784 {
785 	pmd_val(*pmdp) = _SEGMENT_ENTRY_INVALID;
786 }
787 
788 static inline void pte_clear(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
789 {
790 	pte_val(*ptep) = _PAGE_INVALID;
791 }
792 
793 /*
794  * The following pte modification functions only work if
795  * pte_present() is true. Undefined behaviour if not..
796  */
797 static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
798 {
799 	pte_val(pte) &= _PAGE_CHG_MASK;
800 	pte_val(pte) |= pgprot_val(newprot);
801 	/*
802 	 * newprot for PAGE_NONE, PAGE_READ and PAGE_WRITE has the
803 	 * invalid bit set, clear it again for readable, young pages
804 	 */
805 	if ((pte_val(pte) & _PAGE_YOUNG) && (pte_val(pte) & _PAGE_READ))
806 		pte_val(pte) &= ~_PAGE_INVALID;
807 	/*
808 	 * newprot for PAGE_READ and PAGE_WRITE has the page protection
809 	 * bit set, clear it again for writable, dirty pages
810 	 */
811 	if ((pte_val(pte) & _PAGE_DIRTY) && (pte_val(pte) & _PAGE_WRITE))
812 		pte_val(pte) &= ~_PAGE_PROTECT;
813 	return pte;
814 }
815 
816 static inline pte_t pte_wrprotect(pte_t pte)
817 {
818 	pte_val(pte) &= ~_PAGE_WRITE;
819 	pte_val(pte) |= _PAGE_PROTECT;
820 	return pte;
821 }
822 
823 static inline pte_t pte_mkwrite(pte_t pte)
824 {
825 	pte_val(pte) |= _PAGE_WRITE;
826 	if (pte_val(pte) & _PAGE_DIRTY)
827 		pte_val(pte) &= ~_PAGE_PROTECT;
828 	return pte;
829 }
830 
831 static inline pte_t pte_mkclean(pte_t pte)
832 {
833 	pte_val(pte) &= ~_PAGE_DIRTY;
834 	pte_val(pte) |= _PAGE_PROTECT;
835 	return pte;
836 }
837 
838 static inline pte_t pte_mkdirty(pte_t pte)
839 {
840 	pte_val(pte) |= _PAGE_DIRTY | _PAGE_SOFT_DIRTY;
841 	if (pte_val(pte) & _PAGE_WRITE)
842 		pte_val(pte) &= ~_PAGE_PROTECT;
843 	return pte;
844 }
845 
846 static inline pte_t pte_mkold(pte_t pte)
847 {
848 	pte_val(pte) &= ~_PAGE_YOUNG;
849 	pte_val(pte) |= _PAGE_INVALID;
850 	return pte;
851 }
852 
853 static inline pte_t pte_mkyoung(pte_t pte)
854 {
855 	pte_val(pte) |= _PAGE_YOUNG;
856 	if (pte_val(pte) & _PAGE_READ)
857 		pte_val(pte) &= ~_PAGE_INVALID;
858 	return pte;
859 }
860 
861 static inline pte_t pte_mkspecial(pte_t pte)
862 {
863 	pte_val(pte) |= _PAGE_SPECIAL;
864 	return pte;
865 }
866 
867 #ifdef CONFIG_HUGETLB_PAGE
868 static inline pte_t pte_mkhuge(pte_t pte)
869 {
870 	pte_val(pte) |= _PAGE_LARGE;
871 	return pte;
872 }
873 #endif
874 
875 static inline void __ptep_ipte(unsigned long address, pte_t *ptep)
876 {
877 	unsigned long pto = (unsigned long) ptep;
878 
879 	/* Invalidation + global TLB flush for the pte */
880 	asm volatile(
881 		"	ipte	%2,%3"
882 		: "=m" (*ptep) : "m" (*ptep), "a" (pto), "a" (address));
883 }
884 
885 static inline void __ptep_ipte_local(unsigned long address, pte_t *ptep)
886 {
887 	unsigned long pto = (unsigned long) ptep;
888 
889 	/* Invalidation + local TLB flush for the pte */
890 	asm volatile(
891 		"	.insn rrf,0xb2210000,%2,%3,0,1"
892 		: "=m" (*ptep) : "m" (*ptep), "a" (pto), "a" (address));
893 }
894 
895 static inline void __ptep_ipte_range(unsigned long address, int nr, pte_t *ptep)
896 {
897 	unsigned long pto = (unsigned long) ptep;
898 
899 	/* Invalidate a range of ptes + global TLB flush of the ptes */
900 	do {
901 		asm volatile(
902 			"	.insn rrf,0xb2210000,%2,%0,%1,0"
903 			: "+a" (address), "+a" (nr) : "a" (pto) : "memory");
904 	} while (nr != 255);
905 }
906 
907 /*
908  * This is hard to understand. ptep_get_and_clear and ptep_clear_flush
909  * both clear the TLB for the unmapped pte. The reason is that
910  * ptep_get_and_clear is used in common code (e.g. change_pte_range)
911  * to modify an active pte. The sequence is
912  *   1) ptep_get_and_clear
913  *   2) set_pte_at
914  *   3) flush_tlb_range
915  * On s390 the tlb needs to get flushed with the modification of the pte
916  * if the pte is active. The only way how this can be implemented is to
917  * have ptep_get_and_clear do the tlb flush. In exchange flush_tlb_range
918  * is a nop.
919  */
920 pte_t ptep_xchg_direct(struct mm_struct *, unsigned long, pte_t *, pte_t);
921 pte_t ptep_xchg_lazy(struct mm_struct *, unsigned long, pte_t *, pte_t);
922 
923 #define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG
924 static inline int ptep_test_and_clear_young(struct vm_area_struct *vma,
925 					    unsigned long addr, pte_t *ptep)
926 {
927 	pte_t pte = *ptep;
928 
929 	pte = ptep_xchg_direct(vma->vm_mm, addr, ptep, pte_mkold(pte));
930 	return pte_young(pte);
931 }
932 
933 #define __HAVE_ARCH_PTEP_CLEAR_YOUNG_FLUSH
934 static inline int ptep_clear_flush_young(struct vm_area_struct *vma,
935 					 unsigned long address, pte_t *ptep)
936 {
937 	return ptep_test_and_clear_young(vma, address, ptep);
938 }
939 
940 #define __HAVE_ARCH_PTEP_GET_AND_CLEAR
941 static inline pte_t ptep_get_and_clear(struct mm_struct *mm,
942 				       unsigned long addr, pte_t *ptep)
943 {
944 	return ptep_xchg_lazy(mm, addr, ptep, __pte(_PAGE_INVALID));
945 }
946 
947 #define __HAVE_ARCH_PTEP_MODIFY_PROT_TRANSACTION
948 pte_t ptep_modify_prot_start(struct mm_struct *, unsigned long, pte_t *);
949 void ptep_modify_prot_commit(struct mm_struct *, unsigned long, pte_t *, pte_t);
950 
951 #define __HAVE_ARCH_PTEP_CLEAR_FLUSH
952 static inline pte_t ptep_clear_flush(struct vm_area_struct *vma,
953 				     unsigned long addr, pte_t *ptep)
954 {
955 	return ptep_xchg_direct(vma->vm_mm, addr, ptep, __pte(_PAGE_INVALID));
956 }
957 
958 /*
959  * The batched pte unmap code uses ptep_get_and_clear_full to clear the
960  * ptes. Here an optimization is possible. tlb_gather_mmu flushes all
961  * tlbs of an mm if it can guarantee that the ptes of the mm_struct
962  * cannot be accessed while the batched unmap is running. In this case
963  * full==1 and a simple pte_clear is enough. See tlb.h.
964  */
965 #define __HAVE_ARCH_PTEP_GET_AND_CLEAR_FULL
966 static inline pte_t ptep_get_and_clear_full(struct mm_struct *mm,
967 					    unsigned long addr,
968 					    pte_t *ptep, int full)
969 {
970 	if (full) {
971 		pte_t pte = *ptep;
972 		*ptep = __pte(_PAGE_INVALID);
973 		return pte;
974 	}
975 	return ptep_xchg_lazy(mm, addr, ptep, __pte(_PAGE_INVALID));
976 }
977 
978 #define __HAVE_ARCH_PTEP_SET_WRPROTECT
979 static inline void ptep_set_wrprotect(struct mm_struct *mm,
980 				      unsigned long addr, pte_t *ptep)
981 {
982 	pte_t pte = *ptep;
983 
984 	if (pte_write(pte))
985 		ptep_xchg_lazy(mm, addr, ptep, pte_wrprotect(pte));
986 }
987 
988 #define __HAVE_ARCH_PTEP_SET_ACCESS_FLAGS
989 static inline int ptep_set_access_flags(struct vm_area_struct *vma,
990 					unsigned long addr, pte_t *ptep,
991 					pte_t entry, int dirty)
992 {
993 	if (pte_same(*ptep, entry))
994 		return 0;
995 	ptep_xchg_direct(vma->vm_mm, addr, ptep, entry);
996 	return 1;
997 }
998 
999 /*
1000  * Additional functions to handle KVM guest page tables
1001  */
1002 void ptep_set_pte_at(struct mm_struct *mm, unsigned long addr,
1003 		     pte_t *ptep, pte_t entry);
1004 void ptep_set_notify(struct mm_struct *mm, unsigned long addr, pte_t *ptep);
1005 void ptep_notify(struct mm_struct *mm, unsigned long addr, pte_t *ptep);
1006 void ptep_zap_unused(struct mm_struct *mm, unsigned long addr,
1007 		     pte_t *ptep , int reset);
1008 void ptep_zap_key(struct mm_struct *mm, unsigned long addr, pte_t *ptep);
1009 
1010 bool test_and_clear_guest_dirty(struct mm_struct *mm, unsigned long address);
1011 int set_guest_storage_key(struct mm_struct *mm, unsigned long addr,
1012 			  unsigned char key, bool nq);
1013 unsigned char get_guest_storage_key(struct mm_struct *mm, unsigned long addr);
1014 
1015 /*
1016  * Certain architectures need to do special things when PTEs
1017  * within a page table are directly modified.  Thus, the following
1018  * hook is made available.
1019  */
1020 static inline void set_pte_at(struct mm_struct *mm, unsigned long addr,
1021 			      pte_t *ptep, pte_t entry)
1022 {
1023 	if (mm_has_pgste(mm))
1024 		ptep_set_pte_at(mm, addr, ptep, entry);
1025 	else
1026 		*ptep = entry;
1027 }
1028 
1029 /*
1030  * Conversion functions: convert a page and protection to a page entry,
1031  * and a page entry and page directory to the page they refer to.
1032  */
1033 static inline pte_t mk_pte_phys(unsigned long physpage, pgprot_t pgprot)
1034 {
1035 	pte_t __pte;
1036 	pte_val(__pte) = physpage + pgprot_val(pgprot);
1037 	return pte_mkyoung(__pte);
1038 }
1039 
1040 static inline pte_t mk_pte(struct page *page, pgprot_t pgprot)
1041 {
1042 	unsigned long physpage = page_to_phys(page);
1043 	pte_t __pte = mk_pte_phys(physpage, pgprot);
1044 
1045 	if (pte_write(__pte) && PageDirty(page))
1046 		__pte = pte_mkdirty(__pte);
1047 	return __pte;
1048 }
1049 
1050 #define pgd_index(address) (((address) >> PGDIR_SHIFT) & (PTRS_PER_PGD-1))
1051 #define pud_index(address) (((address) >> PUD_SHIFT) & (PTRS_PER_PUD-1))
1052 #define pmd_index(address) (((address) >> PMD_SHIFT) & (PTRS_PER_PMD-1))
1053 #define pte_index(address) (((address) >> PAGE_SHIFT) & (PTRS_PER_PTE-1))
1054 
1055 #define pgd_offset(mm, address) ((mm)->pgd + pgd_index(address))
1056 #define pgd_offset_k(address) pgd_offset(&init_mm, address)
1057 
1058 #define pmd_deref(pmd) (pmd_val(pmd) & _SEGMENT_ENTRY_ORIGIN)
1059 #define pud_deref(pud) (pud_val(pud) & _REGION_ENTRY_ORIGIN)
1060 #define pgd_deref(pgd) (pgd_val(pgd) & _REGION_ENTRY_ORIGIN)
1061 
1062 static inline pud_t *pud_offset(pgd_t *pgd, unsigned long address)
1063 {
1064 	pud_t *pud = (pud_t *) pgd;
1065 	if ((pgd_val(*pgd) & _REGION_ENTRY_TYPE_MASK) == _REGION_ENTRY_TYPE_R2)
1066 		pud = (pud_t *) pgd_deref(*pgd);
1067 	return pud  + pud_index(address);
1068 }
1069 
1070 static inline pmd_t *pmd_offset(pud_t *pud, unsigned long address)
1071 {
1072 	pmd_t *pmd = (pmd_t *) pud;
1073 	if ((pud_val(*pud) & _REGION_ENTRY_TYPE_MASK) == _REGION_ENTRY_TYPE_R3)
1074 		pmd = (pmd_t *) pud_deref(*pud);
1075 	return pmd + pmd_index(address);
1076 }
1077 
1078 #define pfn_pte(pfn,pgprot) mk_pte_phys(__pa((pfn) << PAGE_SHIFT),(pgprot))
1079 #define pte_pfn(x) (pte_val(x) >> PAGE_SHIFT)
1080 #define pte_page(x) pfn_to_page(pte_pfn(x))
1081 
1082 #define pmd_page(pmd) pfn_to_page(pmd_pfn(pmd))
1083 #define pud_page(pud) pfn_to_page(pud_pfn(pud))
1084 
1085 /* Find an entry in the lowest level page table.. */
1086 #define pte_offset(pmd, addr) ((pte_t *) pmd_deref(*(pmd)) + pte_index(addr))
1087 #define pte_offset_kernel(pmd, address) pte_offset(pmd,address)
1088 #define pte_offset_map(pmd, address) pte_offset_kernel(pmd, address)
1089 #define pte_unmap(pte) do { } while (0)
1090 
1091 static inline pmd_t pmd_wrprotect(pmd_t pmd)
1092 {
1093 	pmd_val(pmd) &= ~_SEGMENT_ENTRY_WRITE;
1094 	pmd_val(pmd) |= _SEGMENT_ENTRY_PROTECT;
1095 	return pmd;
1096 }
1097 
1098 static inline pmd_t pmd_mkwrite(pmd_t pmd)
1099 {
1100 	pmd_val(pmd) |= _SEGMENT_ENTRY_WRITE;
1101 	if (pmd_large(pmd) && !(pmd_val(pmd) & _SEGMENT_ENTRY_DIRTY))
1102 		return pmd;
1103 	pmd_val(pmd) &= ~_SEGMENT_ENTRY_PROTECT;
1104 	return pmd;
1105 }
1106 
1107 static inline pmd_t pmd_mkclean(pmd_t pmd)
1108 {
1109 	if (pmd_large(pmd)) {
1110 		pmd_val(pmd) &= ~_SEGMENT_ENTRY_DIRTY;
1111 		pmd_val(pmd) |= _SEGMENT_ENTRY_PROTECT;
1112 	}
1113 	return pmd;
1114 }
1115 
1116 static inline pmd_t pmd_mkdirty(pmd_t pmd)
1117 {
1118 	if (pmd_large(pmd)) {
1119 		pmd_val(pmd) |= _SEGMENT_ENTRY_DIRTY |
1120 				_SEGMENT_ENTRY_SOFT_DIRTY;
1121 		if (pmd_val(pmd) & _SEGMENT_ENTRY_WRITE)
1122 			pmd_val(pmd) &= ~_SEGMENT_ENTRY_PROTECT;
1123 	}
1124 	return pmd;
1125 }
1126 
1127 static inline pud_t pud_wrprotect(pud_t pud)
1128 {
1129 	pud_val(pud) &= ~_REGION3_ENTRY_WRITE;
1130 	pud_val(pud) |= _REGION_ENTRY_PROTECT;
1131 	return pud;
1132 }
1133 
1134 static inline pud_t pud_mkwrite(pud_t pud)
1135 {
1136 	pud_val(pud) |= _REGION3_ENTRY_WRITE;
1137 	if (pud_large(pud) && !(pud_val(pud) & _REGION3_ENTRY_DIRTY))
1138 		return pud;
1139 	pud_val(pud) &= ~_REGION_ENTRY_PROTECT;
1140 	return pud;
1141 }
1142 
1143 static inline pud_t pud_mkclean(pud_t pud)
1144 {
1145 	if (pud_large(pud)) {
1146 		pud_val(pud) &= ~_REGION3_ENTRY_DIRTY;
1147 		pud_val(pud) |= _REGION_ENTRY_PROTECT;
1148 	}
1149 	return pud;
1150 }
1151 
1152 static inline pud_t pud_mkdirty(pud_t pud)
1153 {
1154 	if (pud_large(pud)) {
1155 		pud_val(pud) |= _REGION3_ENTRY_DIRTY |
1156 				_REGION3_ENTRY_SOFT_DIRTY;
1157 		if (pud_val(pud) & _REGION3_ENTRY_WRITE)
1158 			pud_val(pud) &= ~_REGION_ENTRY_PROTECT;
1159 	}
1160 	return pud;
1161 }
1162 
1163 #if defined(CONFIG_TRANSPARENT_HUGEPAGE) || defined(CONFIG_HUGETLB_PAGE)
1164 static inline unsigned long massage_pgprot_pmd(pgprot_t pgprot)
1165 {
1166 	/*
1167 	 * pgprot is PAGE_NONE, PAGE_READ, or PAGE_WRITE (see __Pxxx / __Sxxx)
1168 	 * Convert to segment table entry format.
1169 	 */
1170 	if (pgprot_val(pgprot) == pgprot_val(PAGE_NONE))
1171 		return pgprot_val(SEGMENT_NONE);
1172 	if (pgprot_val(pgprot) == pgprot_val(PAGE_READ))
1173 		return pgprot_val(SEGMENT_READ);
1174 	return pgprot_val(SEGMENT_WRITE);
1175 }
1176 
1177 static inline pmd_t pmd_mkyoung(pmd_t pmd)
1178 {
1179 	if (pmd_large(pmd)) {
1180 		pmd_val(pmd) |= _SEGMENT_ENTRY_YOUNG;
1181 		if (pmd_val(pmd) & _SEGMENT_ENTRY_READ)
1182 			pmd_val(pmd) &= ~_SEGMENT_ENTRY_INVALID;
1183 	}
1184 	return pmd;
1185 }
1186 
1187 static inline pmd_t pmd_mkold(pmd_t pmd)
1188 {
1189 	if (pmd_large(pmd)) {
1190 		pmd_val(pmd) &= ~_SEGMENT_ENTRY_YOUNG;
1191 		pmd_val(pmd) |= _SEGMENT_ENTRY_INVALID;
1192 	}
1193 	return pmd;
1194 }
1195 
1196 static inline pmd_t pmd_modify(pmd_t pmd, pgprot_t newprot)
1197 {
1198 	if (pmd_large(pmd)) {
1199 		pmd_val(pmd) &= _SEGMENT_ENTRY_ORIGIN_LARGE |
1200 			_SEGMENT_ENTRY_DIRTY | _SEGMENT_ENTRY_YOUNG |
1201 			_SEGMENT_ENTRY_LARGE | _SEGMENT_ENTRY_SOFT_DIRTY;
1202 		pmd_val(pmd) |= massage_pgprot_pmd(newprot);
1203 		if (!(pmd_val(pmd) & _SEGMENT_ENTRY_DIRTY))
1204 			pmd_val(pmd) |= _SEGMENT_ENTRY_PROTECT;
1205 		if (!(pmd_val(pmd) & _SEGMENT_ENTRY_YOUNG))
1206 			pmd_val(pmd) |= _SEGMENT_ENTRY_INVALID;
1207 		return pmd;
1208 	}
1209 	pmd_val(pmd) &= _SEGMENT_ENTRY_ORIGIN;
1210 	pmd_val(pmd) |= massage_pgprot_pmd(newprot);
1211 	return pmd;
1212 }
1213 
1214 static inline pmd_t mk_pmd_phys(unsigned long physpage, pgprot_t pgprot)
1215 {
1216 	pmd_t __pmd;
1217 	pmd_val(__pmd) = physpage + massage_pgprot_pmd(pgprot);
1218 	return __pmd;
1219 }
1220 
1221 #endif /* CONFIG_TRANSPARENT_HUGEPAGE || CONFIG_HUGETLB_PAGE */
1222 
1223 static inline void __pmdp_csp(pmd_t *pmdp)
1224 {
1225 	csp((unsigned int *)pmdp + 1, pmd_val(*pmdp),
1226 	    pmd_val(*pmdp) | _SEGMENT_ENTRY_INVALID);
1227 }
1228 
1229 static inline void __pmdp_idte(unsigned long address, pmd_t *pmdp)
1230 {
1231 	unsigned long sto;
1232 
1233 	sto = (unsigned long) pmdp - pmd_index(address) * sizeof(pmd_t);
1234 	asm volatile(
1235 		"	.insn	rrf,0xb98e0000,%2,%3,0,0"
1236 		: "=m" (*pmdp)
1237 		: "m" (*pmdp), "a" (sto), "a" ((address & HPAGE_MASK))
1238 		: "cc" );
1239 }
1240 
1241 static inline void __pudp_idte(unsigned long address, pud_t *pudp)
1242 {
1243 	unsigned long r3o;
1244 
1245 	r3o = (unsigned long) pudp - pud_index(address) * sizeof(pud_t);
1246 	r3o |= _ASCE_TYPE_REGION3;
1247 	asm volatile(
1248 		"	.insn	rrf,0xb98e0000,%2,%3,0,0"
1249 		: "=m" (*pudp)
1250 		: "m" (*pudp), "a" (r3o), "a" ((address & PUD_MASK))
1251 		: "cc");
1252 }
1253 
1254 static inline void __pmdp_idte_local(unsigned long address, pmd_t *pmdp)
1255 {
1256 	unsigned long sto;
1257 
1258 	sto = (unsigned long) pmdp - pmd_index(address) * sizeof(pmd_t);
1259 	asm volatile(
1260 		"	.insn	rrf,0xb98e0000,%2,%3,0,1"
1261 		: "=m" (*pmdp)
1262 		: "m" (*pmdp), "a" (sto), "a" ((address & HPAGE_MASK))
1263 		: "cc" );
1264 }
1265 
1266 static inline void __pudp_idte_local(unsigned long address, pud_t *pudp)
1267 {
1268 	unsigned long r3o;
1269 
1270 	r3o = (unsigned long) pudp - pud_index(address) * sizeof(pud_t);
1271 	r3o |= _ASCE_TYPE_REGION3;
1272 	asm volatile(
1273 		"	.insn	rrf,0xb98e0000,%2,%3,0,1"
1274 		: "=m" (*pudp)
1275 		: "m" (*pudp), "a" (r3o), "a" ((address & PUD_MASK))
1276 		: "cc");
1277 }
1278 
1279 pmd_t pmdp_xchg_direct(struct mm_struct *, unsigned long, pmd_t *, pmd_t);
1280 pmd_t pmdp_xchg_lazy(struct mm_struct *, unsigned long, pmd_t *, pmd_t);
1281 pud_t pudp_xchg_direct(struct mm_struct *, unsigned long, pud_t *, pud_t);
1282 
1283 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
1284 
1285 #define __HAVE_ARCH_PGTABLE_DEPOSIT
1286 void pgtable_trans_huge_deposit(struct mm_struct *mm, pmd_t *pmdp,
1287 				pgtable_t pgtable);
1288 
1289 #define __HAVE_ARCH_PGTABLE_WITHDRAW
1290 pgtable_t pgtable_trans_huge_withdraw(struct mm_struct *mm, pmd_t *pmdp);
1291 
1292 #define  __HAVE_ARCH_PMDP_SET_ACCESS_FLAGS
1293 static inline int pmdp_set_access_flags(struct vm_area_struct *vma,
1294 					unsigned long addr, pmd_t *pmdp,
1295 					pmd_t entry, int dirty)
1296 {
1297 	VM_BUG_ON(addr & ~HPAGE_MASK);
1298 
1299 	entry = pmd_mkyoung(entry);
1300 	if (dirty)
1301 		entry = pmd_mkdirty(entry);
1302 	if (pmd_val(*pmdp) == pmd_val(entry))
1303 		return 0;
1304 	pmdp_xchg_direct(vma->vm_mm, addr, pmdp, entry);
1305 	return 1;
1306 }
1307 
1308 #define __HAVE_ARCH_PMDP_TEST_AND_CLEAR_YOUNG
1309 static inline int pmdp_test_and_clear_young(struct vm_area_struct *vma,
1310 					    unsigned long addr, pmd_t *pmdp)
1311 {
1312 	pmd_t pmd = *pmdp;
1313 
1314 	pmd = pmdp_xchg_direct(vma->vm_mm, addr, pmdp, pmd_mkold(pmd));
1315 	return pmd_young(pmd);
1316 }
1317 
1318 #define __HAVE_ARCH_PMDP_CLEAR_YOUNG_FLUSH
1319 static inline int pmdp_clear_flush_young(struct vm_area_struct *vma,
1320 					 unsigned long addr, pmd_t *pmdp)
1321 {
1322 	VM_BUG_ON(addr & ~HPAGE_MASK);
1323 	return pmdp_test_and_clear_young(vma, addr, pmdp);
1324 }
1325 
1326 static inline void set_pmd_at(struct mm_struct *mm, unsigned long addr,
1327 			      pmd_t *pmdp, pmd_t entry)
1328 {
1329 	*pmdp = entry;
1330 }
1331 
1332 static inline pmd_t pmd_mkhuge(pmd_t pmd)
1333 {
1334 	pmd_val(pmd) |= _SEGMENT_ENTRY_LARGE;
1335 	pmd_val(pmd) |= _SEGMENT_ENTRY_YOUNG;
1336 	pmd_val(pmd) |= _SEGMENT_ENTRY_PROTECT;
1337 	return pmd;
1338 }
1339 
1340 #define __HAVE_ARCH_PMDP_HUGE_GET_AND_CLEAR
1341 static inline pmd_t pmdp_huge_get_and_clear(struct mm_struct *mm,
1342 					    unsigned long addr, pmd_t *pmdp)
1343 {
1344 	return pmdp_xchg_direct(mm, addr, pmdp, __pmd(_SEGMENT_ENTRY_INVALID));
1345 }
1346 
1347 #define __HAVE_ARCH_PMDP_HUGE_GET_AND_CLEAR_FULL
1348 static inline pmd_t pmdp_huge_get_and_clear_full(struct mm_struct *mm,
1349 						 unsigned long addr,
1350 						 pmd_t *pmdp, int full)
1351 {
1352 	if (full) {
1353 		pmd_t pmd = *pmdp;
1354 		*pmdp = __pmd(_SEGMENT_ENTRY_INVALID);
1355 		return pmd;
1356 	}
1357 	return pmdp_xchg_lazy(mm, addr, pmdp, __pmd(_SEGMENT_ENTRY_INVALID));
1358 }
1359 
1360 #define __HAVE_ARCH_PMDP_HUGE_CLEAR_FLUSH
1361 static inline pmd_t pmdp_huge_clear_flush(struct vm_area_struct *vma,
1362 					  unsigned long addr, pmd_t *pmdp)
1363 {
1364 	return pmdp_huge_get_and_clear(vma->vm_mm, addr, pmdp);
1365 }
1366 
1367 #define __HAVE_ARCH_PMDP_INVALIDATE
1368 static inline void pmdp_invalidate(struct vm_area_struct *vma,
1369 				   unsigned long addr, pmd_t *pmdp)
1370 {
1371 	pmdp_xchg_direct(vma->vm_mm, addr, pmdp, __pmd(_SEGMENT_ENTRY_INVALID));
1372 }
1373 
1374 #define __HAVE_ARCH_PMDP_SET_WRPROTECT
1375 static inline void pmdp_set_wrprotect(struct mm_struct *mm,
1376 				      unsigned long addr, pmd_t *pmdp)
1377 {
1378 	pmd_t pmd = *pmdp;
1379 
1380 	if (pmd_write(pmd))
1381 		pmd = pmdp_xchg_lazy(mm, addr, pmdp, pmd_wrprotect(pmd));
1382 }
1383 
1384 static inline pmd_t pmdp_collapse_flush(struct vm_area_struct *vma,
1385 					unsigned long address,
1386 					pmd_t *pmdp)
1387 {
1388 	return pmdp_huge_get_and_clear(vma->vm_mm, address, pmdp);
1389 }
1390 #define pmdp_collapse_flush pmdp_collapse_flush
1391 
1392 #define pfn_pmd(pfn, pgprot)	mk_pmd_phys(__pa((pfn) << PAGE_SHIFT), (pgprot))
1393 #define mk_pmd(page, pgprot)	pfn_pmd(page_to_pfn(page), (pgprot))
1394 
1395 static inline int pmd_trans_huge(pmd_t pmd)
1396 {
1397 	return pmd_val(pmd) & _SEGMENT_ENTRY_LARGE;
1398 }
1399 
1400 #define has_transparent_hugepage has_transparent_hugepage
1401 static inline int has_transparent_hugepage(void)
1402 {
1403 	return MACHINE_HAS_HPAGE ? 1 : 0;
1404 }
1405 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
1406 
1407 /*
1408  * 64 bit swap entry format:
1409  * A page-table entry has some bits we have to treat in a special way.
1410  * Bits 52 and bit 55 have to be zero, otherwise a specification
1411  * exception will occur instead of a page translation exception. The
1412  * specification exception has the bad habit not to store necessary
1413  * information in the lowcore.
1414  * Bits 54 and 63 are used to indicate the page type.
1415  * A swap pte is indicated by bit pattern (pte & 0x201) == 0x200
1416  * This leaves the bits 0-51 and bits 56-62 to store type and offset.
1417  * We use the 5 bits from 57-61 for the type and the 52 bits from 0-51
1418  * for the offset.
1419  * |			  offset			|01100|type |00|
1420  * |0000000000111111111122222222223333333333444444444455|55555|55566|66|
1421  * |0123456789012345678901234567890123456789012345678901|23456|78901|23|
1422  */
1423 
1424 #define __SWP_OFFSET_MASK	((1UL << 52) - 1)
1425 #define __SWP_OFFSET_SHIFT	12
1426 #define __SWP_TYPE_MASK		((1UL << 5) - 1)
1427 #define __SWP_TYPE_SHIFT	2
1428 
1429 static inline pte_t mk_swap_pte(unsigned long type, unsigned long offset)
1430 {
1431 	pte_t pte;
1432 
1433 	pte_val(pte) = _PAGE_INVALID | _PAGE_PROTECT;
1434 	pte_val(pte) |= (offset & __SWP_OFFSET_MASK) << __SWP_OFFSET_SHIFT;
1435 	pte_val(pte) |= (type & __SWP_TYPE_MASK) << __SWP_TYPE_SHIFT;
1436 	return pte;
1437 }
1438 
1439 static inline unsigned long __swp_type(swp_entry_t entry)
1440 {
1441 	return (entry.val >> __SWP_TYPE_SHIFT) & __SWP_TYPE_MASK;
1442 }
1443 
1444 static inline unsigned long __swp_offset(swp_entry_t entry)
1445 {
1446 	return (entry.val >> __SWP_OFFSET_SHIFT) & __SWP_OFFSET_MASK;
1447 }
1448 
1449 static inline swp_entry_t __swp_entry(unsigned long type, unsigned long offset)
1450 {
1451 	return (swp_entry_t) { pte_val(mk_swap_pte(type, offset)) };
1452 }
1453 
1454 #define __pte_to_swp_entry(pte)	((swp_entry_t) { pte_val(pte) })
1455 #define __swp_entry_to_pte(x)	((pte_t) { (x).val })
1456 
1457 #endif /* !__ASSEMBLY__ */
1458 
1459 #define kern_addr_valid(addr)   (1)
1460 
1461 extern int vmem_add_mapping(unsigned long start, unsigned long size);
1462 extern int vmem_remove_mapping(unsigned long start, unsigned long size);
1463 extern int s390_enable_sie(void);
1464 extern int s390_enable_skey(void);
1465 extern void s390_reset_cmma(struct mm_struct *mm);
1466 
1467 /* s390 has a private copy of get unmapped area to deal with cache synonyms */
1468 #define HAVE_ARCH_UNMAPPED_AREA
1469 #define HAVE_ARCH_UNMAPPED_AREA_TOPDOWN
1470 
1471 /*
1472  * No page table caches to initialise
1473  */
1474 static inline void pgtable_cache_init(void) { }
1475 static inline void check_pgt_cache(void) { }
1476 
1477 #include <asm-generic/pgtable.h>
1478 
1479 #endif /* _S390_PAGE_H */
1480