xref: /openbmc/linux/arch/s390/include/asm/pgtable.h (revision 623e9ef6)
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 <asm/bug.h>
32 #include <asm/page.h>
33 
34 extern pgd_t swapper_pg_dir[] __attribute__ ((aligned (4096)));
35 extern void paging_init(void);
36 extern void vmem_map_init(void);
37 
38 /*
39  * The S390 doesn't have any external MMU info: the kernel page
40  * tables contain all the necessary information.
41  */
42 #define update_mmu_cache(vma, address, ptep)     do { } while (0)
43 #define update_mmu_cache_pmd(vma, address, ptep) do { } while (0)
44 
45 /*
46  * ZERO_PAGE is a global shared page that is always zero; used
47  * for zero-mapped memory areas etc..
48  */
49 
50 extern unsigned long empty_zero_page;
51 extern unsigned long zero_page_mask;
52 
53 #define ZERO_PAGE(vaddr) \
54 	(virt_to_page((void *)(empty_zero_page + \
55 	 (((unsigned long)(vaddr)) &zero_page_mask))))
56 #define __HAVE_COLOR_ZERO_PAGE
57 
58 /* TODO: s390 cannot support io_remap_pfn_range... */
59 #endif /* !__ASSEMBLY__ */
60 
61 /*
62  * PMD_SHIFT determines the size of the area a second-level page
63  * table can map
64  * PGDIR_SHIFT determines what a third-level page table entry can map
65  */
66 #define PMD_SHIFT	20
67 #define PUD_SHIFT	31
68 #define PGDIR_SHIFT	42
69 
70 #define PMD_SIZE        (1UL << PMD_SHIFT)
71 #define PMD_MASK        (~(PMD_SIZE-1))
72 #define PUD_SIZE	(1UL << PUD_SHIFT)
73 #define PUD_MASK	(~(PUD_SIZE-1))
74 #define PGDIR_SIZE	(1UL << PGDIR_SHIFT)
75 #define PGDIR_MASK	(~(PGDIR_SIZE-1))
76 
77 /*
78  * entries per page directory level: the S390 is two-level, so
79  * we don't really have any PMD directory physically.
80  * for S390 segment-table entries are combined to one PGD
81  * that leads to 1024 pte per pgd
82  */
83 #define PTRS_PER_PTE	256
84 #define PTRS_PER_PMD	2048
85 #define PTRS_PER_PUD	2048
86 #define PTRS_PER_PGD	2048
87 
88 #define FIRST_USER_ADDRESS  0UL
89 
90 #define pte_ERROR(e) \
91 	printk("%s:%d: bad pte %p.\n", __FILE__, __LINE__, (void *) pte_val(e))
92 #define pmd_ERROR(e) \
93 	printk("%s:%d: bad pmd %p.\n", __FILE__, __LINE__, (void *) pmd_val(e))
94 #define pud_ERROR(e) \
95 	printk("%s:%d: bad pud %p.\n", __FILE__, __LINE__, (void *) pud_val(e))
96 #define pgd_ERROR(e) \
97 	printk("%s:%d: bad pgd %p.\n", __FILE__, __LINE__, (void *) pgd_val(e))
98 
99 #ifndef __ASSEMBLY__
100 /*
101  * The vmalloc and module area will always be on the topmost area of the
102  * kernel mapping. We reserve 128GB (64bit) for vmalloc and modules.
103  * On 64 bit kernels we have a 2GB area at the top of the vmalloc area where
104  * modules will reside. That makes sure that inter module branches always
105  * happen without trampolines and in addition the placement within a 2GB frame
106  * is branch prediction unit friendly.
107  */
108 extern unsigned long VMALLOC_START;
109 extern unsigned long VMALLOC_END;
110 extern struct page *vmemmap;
111 
112 #define VMEM_MAX_PHYS ((unsigned long) vmemmap)
113 
114 extern unsigned long MODULES_VADDR;
115 extern unsigned long MODULES_END;
116 #define MODULES_VADDR	MODULES_VADDR
117 #define MODULES_END	MODULES_END
118 #define MODULES_LEN	(1UL << 31)
119 
120 static inline int is_module_addr(void *addr)
121 {
122 	BUILD_BUG_ON(MODULES_LEN > (1UL << 31));
123 	if (addr < (void *)MODULES_VADDR)
124 		return 0;
125 	if (addr > (void *)MODULES_END)
126 		return 0;
127 	return 1;
128 }
129 
130 /*
131  * A 64 bit pagetable entry of S390 has following format:
132  * |			 PFRA			      |0IPC|  OS  |
133  * 0000000000111111111122222222223333333333444444444455555555556666
134  * 0123456789012345678901234567890123456789012345678901234567890123
135  *
136  * I Page-Invalid Bit:    Page is not available for address-translation
137  * P Page-Protection Bit: Store access not possible for page
138  * C Change-bit override: HW is not required to set change bit
139  *
140  * A 64 bit segmenttable entry of S390 has following format:
141  * |        P-table origin                              |      TT
142  * 0000000000111111111122222222223333333333444444444455555555556666
143  * 0123456789012345678901234567890123456789012345678901234567890123
144  *
145  * I Segment-Invalid Bit:    Segment is not available for address-translation
146  * C Common-Segment Bit:     Segment is not private (PoP 3-30)
147  * P Page-Protection Bit: Store access not possible for page
148  * TT Type 00
149  *
150  * A 64 bit region table entry of S390 has following format:
151  * |        S-table origin                             |   TF  TTTL
152  * 0000000000111111111122222222223333333333444444444455555555556666
153  * 0123456789012345678901234567890123456789012345678901234567890123
154  *
155  * I Segment-Invalid Bit:    Segment is not available for address-translation
156  * TT Type 01
157  * TF
158  * TL Table length
159  *
160  * The 64 bit regiontable origin of S390 has following format:
161  * |      region table origon                          |       DTTL
162  * 0000000000111111111122222222223333333333444444444455555555556666
163  * 0123456789012345678901234567890123456789012345678901234567890123
164  *
165  * X Space-Switch event:
166  * G Segment-Invalid Bit:
167  * P Private-Space Bit:
168  * S Storage-Alteration:
169  * R Real space
170  * TL Table-Length:
171  *
172  * A storage key has the following format:
173  * | ACC |F|R|C|0|
174  *  0   3 4 5 6 7
175  * ACC: access key
176  * F  : fetch protection bit
177  * R  : referenced bit
178  * C  : changed bit
179  */
180 
181 /* Hardware bits in the page table entry */
182 #define _PAGE_PROTECT	0x200		/* HW read-only bit  */
183 #define _PAGE_INVALID	0x400		/* HW invalid bit    */
184 #define _PAGE_LARGE	0x800		/* Bit to mark a large pte */
185 
186 /* Software bits in the page table entry */
187 #define _PAGE_PRESENT	0x001		/* SW pte present bit */
188 #define _PAGE_YOUNG	0x004		/* SW pte young bit */
189 #define _PAGE_DIRTY	0x008		/* SW pte dirty bit */
190 #define _PAGE_READ	0x010		/* SW pte read bit */
191 #define _PAGE_WRITE	0x020		/* SW pte write bit */
192 #define _PAGE_SPECIAL	0x040		/* SW associated with special page */
193 #define _PAGE_UNUSED	0x080		/* SW bit for pgste usage state */
194 #define __HAVE_ARCH_PTE_SPECIAL
195 
196 #ifdef CONFIG_MEM_SOFT_DIRTY
197 #define _PAGE_SOFT_DIRTY 0x002		/* SW pte soft dirty bit */
198 #else
199 #define _PAGE_SOFT_DIRTY 0x000
200 #endif
201 
202 /* Set of bits not changed in pte_modify */
203 #define _PAGE_CHG_MASK		(PAGE_MASK | _PAGE_SPECIAL | _PAGE_DIRTY | \
204 				 _PAGE_YOUNG | _PAGE_SOFT_DIRTY)
205 
206 /*
207  * handle_pte_fault uses pte_present and pte_none to find out the pte type
208  * WITHOUT holding the page table lock. The _PAGE_PRESENT bit is used to
209  * distinguish present from not-present ptes. It is changed only with the page
210  * table lock held.
211  *
212  * The following table gives the different possible bit combinations for
213  * the pte hardware and software bits in the last 12 bits of a pte
214  * (. unassigned bit, x don't care, t swap type):
215  *
216  *				842100000000
217  *				000084210000
218  *				000000008421
219  *				.IR.uswrdy.p
220  * empty			.10.00000000
221  * swap				.11..ttttt.0
222  * prot-none, clean, old	.11.xx0000.1
223  * prot-none, clean, young	.11.xx0001.1
224  * prot-none, dirty, old	.10.xx0010.1
225  * prot-none, dirty, young	.10.xx0011.1
226  * read-only, clean, old	.11.xx0100.1
227  * read-only, clean, young	.01.xx0101.1
228  * read-only, dirty, old	.11.xx0110.1
229  * read-only, dirty, young	.01.xx0111.1
230  * read-write, clean, old	.11.xx1100.1
231  * read-write, clean, young	.01.xx1101.1
232  * read-write, dirty, old	.10.xx1110.1
233  * read-write, dirty, young	.00.xx1111.1
234  * HW-bits: R read-only, I invalid
235  * SW-bits: p present, y young, d dirty, r read, w write, s special,
236  *	    u unused, l large
237  *
238  * pte_none    is true for the bit pattern .10.00000000, pte == 0x400
239  * pte_swap    is true for the bit pattern .11..ooooo.0, (pte & 0x201) == 0x200
240  * pte_present is true for the bit pattern .xx.xxxxxx.1, (pte & 0x001) == 0x001
241  */
242 
243 /* Bits in the segment/region table address-space-control-element */
244 #define _ASCE_ORIGIN		~0xfffUL/* segment table origin		    */
245 #define _ASCE_PRIVATE_SPACE	0x100	/* private space control	    */
246 #define _ASCE_ALT_EVENT		0x80	/* storage alteration event control */
247 #define _ASCE_SPACE_SWITCH	0x40	/* space switch event		    */
248 #define _ASCE_REAL_SPACE	0x20	/* real space control		    */
249 #define _ASCE_TYPE_MASK		0x0c	/* asce table type mask		    */
250 #define _ASCE_TYPE_REGION1	0x0c	/* region first table type	    */
251 #define _ASCE_TYPE_REGION2	0x08	/* region second table type	    */
252 #define _ASCE_TYPE_REGION3	0x04	/* region third table type	    */
253 #define _ASCE_TYPE_SEGMENT	0x00	/* segment table type		    */
254 #define _ASCE_TABLE_LENGTH	0x03	/* region table length		    */
255 
256 /* Bits in the region table entry */
257 #define _REGION_ENTRY_ORIGIN	~0xfffUL/* region/segment table origin	    */
258 #define _REGION_ENTRY_PROTECT	0x200	/* region protection bit	    */
259 #define _REGION_ENTRY_INVALID	0x20	/* invalid region table entry	    */
260 #define _REGION_ENTRY_TYPE_MASK	0x0c	/* region/segment table type mask   */
261 #define _REGION_ENTRY_TYPE_R1	0x0c	/* region first table type	    */
262 #define _REGION_ENTRY_TYPE_R2	0x08	/* region second table type	    */
263 #define _REGION_ENTRY_TYPE_R3	0x04	/* region third table type	    */
264 #define _REGION_ENTRY_LENGTH	0x03	/* region third length		    */
265 
266 #define _REGION1_ENTRY		(_REGION_ENTRY_TYPE_R1 | _REGION_ENTRY_LENGTH)
267 #define _REGION1_ENTRY_EMPTY	(_REGION_ENTRY_TYPE_R1 | _REGION_ENTRY_INVALID)
268 #define _REGION2_ENTRY		(_REGION_ENTRY_TYPE_R2 | _REGION_ENTRY_LENGTH)
269 #define _REGION2_ENTRY_EMPTY	(_REGION_ENTRY_TYPE_R2 | _REGION_ENTRY_INVALID)
270 #define _REGION3_ENTRY		(_REGION_ENTRY_TYPE_R3 | _REGION_ENTRY_LENGTH)
271 #define _REGION3_ENTRY_EMPTY	(_REGION_ENTRY_TYPE_R3 | _REGION_ENTRY_INVALID)
272 
273 #define _REGION3_ENTRY_LARGE	0x400	/* RTTE-format control, large page  */
274 #define _REGION3_ENTRY_RO	0x200	/* page protection bit		    */
275 
276 /* Bits in the segment table entry */
277 #define _SEGMENT_ENTRY_BITS	0xfffffffffffffe33UL
278 #define _SEGMENT_ENTRY_BITS_LARGE 0xfffffffffff0ff33UL
279 #define _SEGMENT_ENTRY_ORIGIN_LARGE ~0xfffffUL /* large page address	    */
280 #define _SEGMENT_ENTRY_ORIGIN	~0x7ffUL/* segment table origin		    */
281 #define _SEGMENT_ENTRY_PROTECT	0x200	/* page protection bit		    */
282 #define _SEGMENT_ENTRY_INVALID	0x20	/* invalid segment table entry	    */
283 
284 #define _SEGMENT_ENTRY		(0)
285 #define _SEGMENT_ENTRY_EMPTY	(_SEGMENT_ENTRY_INVALID)
286 
287 #define _SEGMENT_ENTRY_DIRTY	0x2000	/* SW segment dirty bit */
288 #define _SEGMENT_ENTRY_YOUNG	0x1000	/* SW segment young bit */
289 #define _SEGMENT_ENTRY_LARGE	0x0400	/* STE-format control, large page */
290 #define _SEGMENT_ENTRY_READ	0x0002	/* SW segment read bit */
291 #define _SEGMENT_ENTRY_WRITE	0x0001	/* SW segment write bit */
292 
293 #ifdef CONFIG_MEM_SOFT_DIRTY
294 #define _SEGMENT_ENTRY_SOFT_DIRTY 0x4000 /* SW segment soft dirty bit */
295 #else
296 #define _SEGMENT_ENTRY_SOFT_DIRTY 0x0000 /* SW segment soft dirty bit */
297 #endif
298 
299 /*
300  * Segment table entry encoding (R = read-only, I = invalid, y = young bit):
301  *				dy..R...I...rw
302  * prot-none, clean, old	00..1...1...00
303  * prot-none, clean, young	01..1...1...00
304  * prot-none, dirty, old	10..1...1...00
305  * prot-none, dirty, young	11..1...1...00
306  * read-only, clean, old	00..1...1...10
307  * read-only, clean, young	01..1...0...10
308  * read-only, dirty, old	10..1...1...10
309  * read-only, dirty, young	11..1...0...10
310  * read-write, clean, old	00..1...1...11
311  * read-write, clean, young	01..1...0...11
312  * read-write, dirty, old	10..0...1...11
313  * read-write, dirty, young	11..0...0...11
314  * The segment table origin is used to distinguish empty (origin==0) from
315  * read-write, old segment table entries (origin!=0)
316  * HW-bits: R read-only, I invalid
317  * SW-bits: y young, d dirty, r read, w write
318  */
319 
320 /* Page status table bits for virtualization */
321 #define PGSTE_ACC_BITS	0xf000000000000000UL
322 #define PGSTE_FP_BIT	0x0800000000000000UL
323 #define PGSTE_PCL_BIT	0x0080000000000000UL
324 #define PGSTE_HR_BIT	0x0040000000000000UL
325 #define PGSTE_HC_BIT	0x0020000000000000UL
326 #define PGSTE_GR_BIT	0x0004000000000000UL
327 #define PGSTE_GC_BIT	0x0002000000000000UL
328 #define PGSTE_UC_BIT	0x0000800000000000UL	/* user dirty (migration) */
329 #define PGSTE_IN_BIT	0x0000400000000000UL	/* IPTE notify bit */
330 
331 /* Guest Page State used for virtualization */
332 #define _PGSTE_GPS_ZERO		0x0000000080000000UL
333 #define _PGSTE_GPS_USAGE_MASK	0x0000000003000000UL
334 #define _PGSTE_GPS_USAGE_STABLE 0x0000000000000000UL
335 #define _PGSTE_GPS_USAGE_UNUSED 0x0000000001000000UL
336 
337 /*
338  * A user page table pointer has the space-switch-event bit, the
339  * private-space-control bit and the storage-alteration-event-control
340  * bit set. A kernel page table pointer doesn't need them.
341  */
342 #define _ASCE_USER_BITS		(_ASCE_SPACE_SWITCH | _ASCE_PRIVATE_SPACE | \
343 				 _ASCE_ALT_EVENT)
344 
345 /*
346  * Page protection definitions.
347  */
348 #define PAGE_NONE	__pgprot(_PAGE_PRESENT | _PAGE_INVALID)
349 #define PAGE_READ	__pgprot(_PAGE_PRESENT | _PAGE_READ | \
350 				 _PAGE_INVALID | _PAGE_PROTECT)
351 #define PAGE_WRITE	__pgprot(_PAGE_PRESENT | _PAGE_READ | _PAGE_WRITE | \
352 				 _PAGE_INVALID | _PAGE_PROTECT)
353 
354 #define PAGE_SHARED	__pgprot(_PAGE_PRESENT | _PAGE_READ | _PAGE_WRITE | \
355 				 _PAGE_YOUNG | _PAGE_DIRTY)
356 #define PAGE_KERNEL	__pgprot(_PAGE_PRESENT | _PAGE_READ | _PAGE_WRITE | \
357 				 _PAGE_YOUNG | _PAGE_DIRTY)
358 #define PAGE_KERNEL_RO	__pgprot(_PAGE_PRESENT | _PAGE_READ | _PAGE_YOUNG | \
359 				 _PAGE_PROTECT)
360 
361 /*
362  * On s390 the page table entry has an invalid bit and a read-only bit.
363  * Read permission implies execute permission and write permission
364  * implies read permission.
365  */
366          /*xwr*/
367 #define __P000	PAGE_NONE
368 #define __P001	PAGE_READ
369 #define __P010	PAGE_READ
370 #define __P011	PAGE_READ
371 #define __P100	PAGE_READ
372 #define __P101	PAGE_READ
373 #define __P110	PAGE_READ
374 #define __P111	PAGE_READ
375 
376 #define __S000	PAGE_NONE
377 #define __S001	PAGE_READ
378 #define __S010	PAGE_WRITE
379 #define __S011	PAGE_WRITE
380 #define __S100	PAGE_READ
381 #define __S101	PAGE_READ
382 #define __S110	PAGE_WRITE
383 #define __S111	PAGE_WRITE
384 
385 /*
386  * Segment entry (large page) protection definitions.
387  */
388 #define SEGMENT_NONE	__pgprot(_SEGMENT_ENTRY_INVALID | \
389 				 _SEGMENT_ENTRY_PROTECT)
390 #define SEGMENT_READ	__pgprot(_SEGMENT_ENTRY_PROTECT | \
391 				 _SEGMENT_ENTRY_READ)
392 #define SEGMENT_WRITE	__pgprot(_SEGMENT_ENTRY_READ | \
393 				 _SEGMENT_ENTRY_WRITE)
394 
395 static inline int mm_has_pgste(struct mm_struct *mm)
396 {
397 #ifdef CONFIG_PGSTE
398 	if (unlikely(mm->context.has_pgste))
399 		return 1;
400 #endif
401 	return 0;
402 }
403 
404 static inline int mm_alloc_pgste(struct mm_struct *mm)
405 {
406 #ifdef CONFIG_PGSTE
407 	if (unlikely(mm->context.alloc_pgste))
408 		return 1;
409 #endif
410 	return 0;
411 }
412 
413 /*
414  * In the case that a guest uses storage keys
415  * faults should no longer be backed by zero pages
416  */
417 #define mm_forbids_zeropage mm_use_skey
418 static inline int mm_use_skey(struct mm_struct *mm)
419 {
420 #ifdef CONFIG_PGSTE
421 	if (mm->context.use_skey)
422 		return 1;
423 #endif
424 	return 0;
425 }
426 
427 /*
428  * pgd/pmd/pte query functions
429  */
430 static inline int pgd_present(pgd_t pgd)
431 {
432 	if ((pgd_val(pgd) & _REGION_ENTRY_TYPE_MASK) < _REGION_ENTRY_TYPE_R2)
433 		return 1;
434 	return (pgd_val(pgd) & _REGION_ENTRY_ORIGIN) != 0UL;
435 }
436 
437 static inline int pgd_none(pgd_t pgd)
438 {
439 	if ((pgd_val(pgd) & _REGION_ENTRY_TYPE_MASK) < _REGION_ENTRY_TYPE_R2)
440 		return 0;
441 	return (pgd_val(pgd) & _REGION_ENTRY_INVALID) != 0UL;
442 }
443 
444 static inline int pgd_bad(pgd_t pgd)
445 {
446 	/*
447 	 * With dynamic page table levels the pgd can be a region table
448 	 * entry or a segment table entry. Check for the bit that are
449 	 * invalid for either table entry.
450 	 */
451 	unsigned long mask =
452 		~_SEGMENT_ENTRY_ORIGIN & ~_REGION_ENTRY_INVALID &
453 		~_REGION_ENTRY_TYPE_MASK & ~_REGION_ENTRY_LENGTH;
454 	return (pgd_val(pgd) & mask) != 0;
455 }
456 
457 static inline int pud_present(pud_t pud)
458 {
459 	if ((pud_val(pud) & _REGION_ENTRY_TYPE_MASK) < _REGION_ENTRY_TYPE_R3)
460 		return 1;
461 	return (pud_val(pud) & _REGION_ENTRY_ORIGIN) != 0UL;
462 }
463 
464 static inline int pud_none(pud_t pud)
465 {
466 	if ((pud_val(pud) & _REGION_ENTRY_TYPE_MASK) < _REGION_ENTRY_TYPE_R3)
467 		return 0;
468 	return (pud_val(pud) & _REGION_ENTRY_INVALID) != 0UL;
469 }
470 
471 static inline int pud_large(pud_t pud)
472 {
473 	if ((pud_val(pud) & _REGION_ENTRY_TYPE_MASK) != _REGION_ENTRY_TYPE_R3)
474 		return 0;
475 	return !!(pud_val(pud) & _REGION3_ENTRY_LARGE);
476 }
477 
478 static inline int pud_bad(pud_t pud)
479 {
480 	/*
481 	 * With dynamic page table levels the pud can be a region table
482 	 * entry or a segment table entry. Check for the bit that are
483 	 * invalid for either table entry.
484 	 */
485 	unsigned long mask =
486 		~_SEGMENT_ENTRY_ORIGIN & ~_REGION_ENTRY_INVALID &
487 		~_REGION_ENTRY_TYPE_MASK & ~_REGION_ENTRY_LENGTH;
488 	return (pud_val(pud) & mask) != 0;
489 }
490 
491 static inline int pmd_present(pmd_t pmd)
492 {
493 	return pmd_val(pmd) != _SEGMENT_ENTRY_INVALID;
494 }
495 
496 static inline int pmd_none(pmd_t pmd)
497 {
498 	return pmd_val(pmd) == _SEGMENT_ENTRY_INVALID;
499 }
500 
501 static inline int pmd_large(pmd_t pmd)
502 {
503 	return (pmd_val(pmd) & _SEGMENT_ENTRY_LARGE) != 0;
504 }
505 
506 static inline unsigned long pmd_pfn(pmd_t pmd)
507 {
508 	unsigned long origin_mask;
509 
510 	origin_mask = _SEGMENT_ENTRY_ORIGIN;
511 	if (pmd_large(pmd))
512 		origin_mask = _SEGMENT_ENTRY_ORIGIN_LARGE;
513 	return (pmd_val(pmd) & origin_mask) >> PAGE_SHIFT;
514 }
515 
516 static inline int pmd_bad(pmd_t pmd)
517 {
518 	if (pmd_large(pmd))
519 		return (pmd_val(pmd) & ~_SEGMENT_ENTRY_BITS_LARGE) != 0;
520 	return (pmd_val(pmd) & ~_SEGMENT_ENTRY_BITS) != 0;
521 }
522 
523 #define __HAVE_ARCH_PMD_WRITE
524 static inline int pmd_write(pmd_t pmd)
525 {
526 	return (pmd_val(pmd) & _SEGMENT_ENTRY_WRITE) != 0;
527 }
528 
529 static inline int pmd_dirty(pmd_t pmd)
530 {
531 	int dirty = 1;
532 	if (pmd_large(pmd))
533 		dirty = (pmd_val(pmd) & _SEGMENT_ENTRY_DIRTY) != 0;
534 	return dirty;
535 }
536 
537 static inline int pmd_young(pmd_t pmd)
538 {
539 	int young = 1;
540 	if (pmd_large(pmd))
541 		young = (pmd_val(pmd) & _SEGMENT_ENTRY_YOUNG) != 0;
542 	return young;
543 }
544 
545 static inline int pte_present(pte_t pte)
546 {
547 	/* Bit pattern: (pte & 0x001) == 0x001 */
548 	return (pte_val(pte) & _PAGE_PRESENT) != 0;
549 }
550 
551 static inline int pte_none(pte_t pte)
552 {
553 	/* Bit pattern: pte == 0x400 */
554 	return pte_val(pte) == _PAGE_INVALID;
555 }
556 
557 static inline int pte_swap(pte_t pte)
558 {
559 	/* Bit pattern: (pte & 0x201) == 0x200 */
560 	return (pte_val(pte) & (_PAGE_PROTECT | _PAGE_PRESENT))
561 		== _PAGE_PROTECT;
562 }
563 
564 static inline int pte_special(pte_t pte)
565 {
566 	return (pte_val(pte) & _PAGE_SPECIAL);
567 }
568 
569 #define __HAVE_ARCH_PTE_SAME
570 static inline int pte_same(pte_t a, pte_t b)
571 {
572 	return pte_val(a) == pte_val(b);
573 }
574 
575 #ifdef CONFIG_NUMA_BALANCING
576 static inline int pte_protnone(pte_t pte)
577 {
578 	return pte_present(pte) && !(pte_val(pte) & _PAGE_READ);
579 }
580 
581 static inline int pmd_protnone(pmd_t pmd)
582 {
583 	/* pmd_large(pmd) implies pmd_present(pmd) */
584 	return pmd_large(pmd) && !(pmd_val(pmd) & _SEGMENT_ENTRY_READ);
585 }
586 #endif
587 
588 static inline int pte_soft_dirty(pte_t pte)
589 {
590 	return pte_val(pte) & _PAGE_SOFT_DIRTY;
591 }
592 #define pte_swp_soft_dirty pte_soft_dirty
593 
594 static inline pte_t pte_mksoft_dirty(pte_t pte)
595 {
596 	pte_val(pte) |= _PAGE_SOFT_DIRTY;
597 	return pte;
598 }
599 #define pte_swp_mksoft_dirty pte_mksoft_dirty
600 
601 static inline pte_t pte_clear_soft_dirty(pte_t pte)
602 {
603 	pte_val(pte) &= ~_PAGE_SOFT_DIRTY;
604 	return pte;
605 }
606 #define pte_swp_clear_soft_dirty pte_clear_soft_dirty
607 
608 static inline int pmd_soft_dirty(pmd_t pmd)
609 {
610 	return pmd_val(pmd) & _SEGMENT_ENTRY_SOFT_DIRTY;
611 }
612 
613 static inline pmd_t pmd_mksoft_dirty(pmd_t pmd)
614 {
615 	pmd_val(pmd) |= _SEGMENT_ENTRY_SOFT_DIRTY;
616 	return pmd;
617 }
618 
619 static inline pmd_t pmd_clear_soft_dirty(pmd_t pmd)
620 {
621 	pmd_val(pmd) &= ~_SEGMENT_ENTRY_SOFT_DIRTY;
622 	return pmd;
623 }
624 
625 /*
626  * query functions pte_write/pte_dirty/pte_young only work if
627  * pte_present() is true. Undefined behaviour if not..
628  */
629 static inline int pte_write(pte_t pte)
630 {
631 	return (pte_val(pte) & _PAGE_WRITE) != 0;
632 }
633 
634 static inline int pte_dirty(pte_t pte)
635 {
636 	return (pte_val(pte) & _PAGE_DIRTY) != 0;
637 }
638 
639 static inline int pte_young(pte_t pte)
640 {
641 	return (pte_val(pte) & _PAGE_YOUNG) != 0;
642 }
643 
644 #define __HAVE_ARCH_PTE_UNUSED
645 static inline int pte_unused(pte_t pte)
646 {
647 	return pte_val(pte) & _PAGE_UNUSED;
648 }
649 
650 /*
651  * pgd/pmd/pte modification functions
652  */
653 
654 static inline void pgd_clear(pgd_t *pgd)
655 {
656 	if ((pgd_val(*pgd) & _REGION_ENTRY_TYPE_MASK) == _REGION_ENTRY_TYPE_R2)
657 		pgd_val(*pgd) = _REGION2_ENTRY_EMPTY;
658 }
659 
660 static inline void pud_clear(pud_t *pud)
661 {
662 	if ((pud_val(*pud) & _REGION_ENTRY_TYPE_MASK) == _REGION_ENTRY_TYPE_R3)
663 		pud_val(*pud) = _REGION3_ENTRY_EMPTY;
664 }
665 
666 static inline void pmd_clear(pmd_t *pmdp)
667 {
668 	pmd_val(*pmdp) = _SEGMENT_ENTRY_INVALID;
669 }
670 
671 static inline void pte_clear(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
672 {
673 	pte_val(*ptep) = _PAGE_INVALID;
674 }
675 
676 /*
677  * The following pte modification functions only work if
678  * pte_present() is true. Undefined behaviour if not..
679  */
680 static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
681 {
682 	pte_val(pte) &= _PAGE_CHG_MASK;
683 	pte_val(pte) |= pgprot_val(newprot);
684 	/*
685 	 * newprot for PAGE_NONE, PAGE_READ and PAGE_WRITE has the
686 	 * invalid bit set, clear it again for readable, young pages
687 	 */
688 	if ((pte_val(pte) & _PAGE_YOUNG) && (pte_val(pte) & _PAGE_READ))
689 		pte_val(pte) &= ~_PAGE_INVALID;
690 	/*
691 	 * newprot for PAGE_READ and PAGE_WRITE has the page protection
692 	 * bit set, clear it again for writable, dirty pages
693 	 */
694 	if ((pte_val(pte) & _PAGE_DIRTY) && (pte_val(pte) & _PAGE_WRITE))
695 		pte_val(pte) &= ~_PAGE_PROTECT;
696 	return pte;
697 }
698 
699 static inline pte_t pte_wrprotect(pte_t pte)
700 {
701 	pte_val(pte) &= ~_PAGE_WRITE;
702 	pte_val(pte) |= _PAGE_PROTECT;
703 	return pte;
704 }
705 
706 static inline pte_t pte_mkwrite(pte_t pte)
707 {
708 	pte_val(pte) |= _PAGE_WRITE;
709 	if (pte_val(pte) & _PAGE_DIRTY)
710 		pte_val(pte) &= ~_PAGE_PROTECT;
711 	return pte;
712 }
713 
714 static inline pte_t pte_mkclean(pte_t pte)
715 {
716 	pte_val(pte) &= ~_PAGE_DIRTY;
717 	pte_val(pte) |= _PAGE_PROTECT;
718 	return pte;
719 }
720 
721 static inline pte_t pte_mkdirty(pte_t pte)
722 {
723 	pte_val(pte) |= _PAGE_DIRTY | _PAGE_SOFT_DIRTY;
724 	if (pte_val(pte) & _PAGE_WRITE)
725 		pte_val(pte) &= ~_PAGE_PROTECT;
726 	return pte;
727 }
728 
729 static inline pte_t pte_mkold(pte_t pte)
730 {
731 	pte_val(pte) &= ~_PAGE_YOUNG;
732 	pte_val(pte) |= _PAGE_INVALID;
733 	return pte;
734 }
735 
736 static inline pte_t pte_mkyoung(pte_t pte)
737 {
738 	pte_val(pte) |= _PAGE_YOUNG;
739 	if (pte_val(pte) & _PAGE_READ)
740 		pte_val(pte) &= ~_PAGE_INVALID;
741 	return pte;
742 }
743 
744 static inline pte_t pte_mkspecial(pte_t pte)
745 {
746 	pte_val(pte) |= _PAGE_SPECIAL;
747 	return pte;
748 }
749 
750 #ifdef CONFIG_HUGETLB_PAGE
751 static inline pte_t pte_mkhuge(pte_t pte)
752 {
753 	pte_val(pte) |= _PAGE_LARGE;
754 	return pte;
755 }
756 #endif
757 
758 static inline void __ptep_ipte(unsigned long address, pte_t *ptep)
759 {
760 	unsigned long pto = (unsigned long) ptep;
761 
762 	/* Invalidation + global TLB flush for the pte */
763 	asm volatile(
764 		"	ipte	%2,%3"
765 		: "=m" (*ptep) : "m" (*ptep), "a" (pto), "a" (address));
766 }
767 
768 static inline void __ptep_ipte_local(unsigned long address, pte_t *ptep)
769 {
770 	unsigned long pto = (unsigned long) ptep;
771 
772 	/* Invalidation + local TLB flush for the pte */
773 	asm volatile(
774 		"	.insn rrf,0xb2210000,%2,%3,0,1"
775 		: "=m" (*ptep) : "m" (*ptep), "a" (pto), "a" (address));
776 }
777 
778 static inline void __ptep_ipte_range(unsigned long address, int nr, pte_t *ptep)
779 {
780 	unsigned long pto = (unsigned long) ptep;
781 
782 	/* Invalidate a range of ptes + global TLB flush of the ptes */
783 	do {
784 		asm volatile(
785 			"	.insn rrf,0xb2210000,%2,%0,%1,0"
786 			: "+a" (address), "+a" (nr) : "a" (pto) : "memory");
787 	} while (nr != 255);
788 }
789 
790 /*
791  * This is hard to understand. ptep_get_and_clear and ptep_clear_flush
792  * both clear the TLB for the unmapped pte. The reason is that
793  * ptep_get_and_clear is used in common code (e.g. change_pte_range)
794  * to modify an active pte. The sequence is
795  *   1) ptep_get_and_clear
796  *   2) set_pte_at
797  *   3) flush_tlb_range
798  * On s390 the tlb needs to get flushed with the modification of the pte
799  * if the pte is active. The only way how this can be implemented is to
800  * have ptep_get_and_clear do the tlb flush. In exchange flush_tlb_range
801  * is a nop.
802  */
803 pte_t ptep_xchg_direct(struct mm_struct *, unsigned long, pte_t *, pte_t);
804 pte_t ptep_xchg_lazy(struct mm_struct *, unsigned long, pte_t *, pte_t);
805 
806 #define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG
807 static inline int ptep_test_and_clear_young(struct vm_area_struct *vma,
808 					    unsigned long addr, pte_t *ptep)
809 {
810 	pte_t pte = *ptep;
811 
812 	pte = ptep_xchg_direct(vma->vm_mm, addr, ptep, pte_mkold(pte));
813 	return pte_young(pte);
814 }
815 
816 #define __HAVE_ARCH_PTEP_CLEAR_YOUNG_FLUSH
817 static inline int ptep_clear_flush_young(struct vm_area_struct *vma,
818 					 unsigned long address, pte_t *ptep)
819 {
820 	return ptep_test_and_clear_young(vma, address, ptep);
821 }
822 
823 #define __HAVE_ARCH_PTEP_GET_AND_CLEAR
824 static inline pte_t ptep_get_and_clear(struct mm_struct *mm,
825 				       unsigned long addr, pte_t *ptep)
826 {
827 	return ptep_xchg_lazy(mm, addr, ptep, __pte(_PAGE_INVALID));
828 }
829 
830 #define __HAVE_ARCH_PTEP_MODIFY_PROT_TRANSACTION
831 pte_t ptep_modify_prot_start(struct mm_struct *, unsigned long, pte_t *);
832 void ptep_modify_prot_commit(struct mm_struct *, unsigned long, pte_t *, pte_t);
833 
834 #define __HAVE_ARCH_PTEP_CLEAR_FLUSH
835 static inline pte_t ptep_clear_flush(struct vm_area_struct *vma,
836 				     unsigned long addr, pte_t *ptep)
837 {
838 	return ptep_xchg_direct(vma->vm_mm, addr, ptep, __pte(_PAGE_INVALID));
839 }
840 
841 /*
842  * The batched pte unmap code uses ptep_get_and_clear_full to clear the
843  * ptes. Here an optimization is possible. tlb_gather_mmu flushes all
844  * tlbs of an mm if it can guarantee that the ptes of the mm_struct
845  * cannot be accessed while the batched unmap is running. In this case
846  * full==1 and a simple pte_clear is enough. See tlb.h.
847  */
848 #define __HAVE_ARCH_PTEP_GET_AND_CLEAR_FULL
849 static inline pte_t ptep_get_and_clear_full(struct mm_struct *mm,
850 					    unsigned long addr,
851 					    pte_t *ptep, int full)
852 {
853 	if (full) {
854 		pte_t pte = *ptep;
855 		*ptep = __pte(_PAGE_INVALID);
856 		return pte;
857 	}
858 	return ptep_xchg_lazy(mm, addr, ptep, __pte(_PAGE_INVALID));
859 }
860 
861 #define __HAVE_ARCH_PTEP_SET_WRPROTECT
862 static inline void ptep_set_wrprotect(struct mm_struct *mm,
863 				      unsigned long addr, pte_t *ptep)
864 {
865 	pte_t pte = *ptep;
866 
867 	if (pte_write(pte))
868 		ptep_xchg_lazy(mm, addr, ptep, pte_wrprotect(pte));
869 }
870 
871 #define __HAVE_ARCH_PTEP_SET_ACCESS_FLAGS
872 static inline int ptep_set_access_flags(struct vm_area_struct *vma,
873 					unsigned long addr, pte_t *ptep,
874 					pte_t entry, int dirty)
875 {
876 	if (pte_same(*ptep, entry))
877 		return 0;
878 	ptep_xchg_direct(vma->vm_mm, addr, ptep, entry);
879 	return 1;
880 }
881 
882 /*
883  * Additional functions to handle KVM guest page tables
884  */
885 void ptep_set_pte_at(struct mm_struct *mm, unsigned long addr,
886 		     pte_t *ptep, pte_t entry);
887 void ptep_set_notify(struct mm_struct *mm, unsigned long addr, pte_t *ptep);
888 void ptep_notify(struct mm_struct *mm, unsigned long addr, pte_t *ptep);
889 void ptep_zap_unused(struct mm_struct *mm, unsigned long addr,
890 		     pte_t *ptep , int reset);
891 void ptep_zap_key(struct mm_struct *mm, unsigned long addr, pte_t *ptep);
892 
893 bool test_and_clear_guest_dirty(struct mm_struct *mm, unsigned long address);
894 int set_guest_storage_key(struct mm_struct *mm, unsigned long addr,
895 			  unsigned char key, bool nq);
896 unsigned char get_guest_storage_key(struct mm_struct *mm, unsigned long addr);
897 
898 /*
899  * Certain architectures need to do special things when PTEs
900  * within a page table are directly modified.  Thus, the following
901  * hook is made available.
902  */
903 static inline void set_pte_at(struct mm_struct *mm, unsigned long addr,
904 			      pte_t *ptep, pte_t entry)
905 {
906 	if (mm_has_pgste(mm))
907 		ptep_set_pte_at(mm, addr, ptep, entry);
908 	else
909 		*ptep = entry;
910 }
911 
912 /*
913  * Conversion functions: convert a page and protection to a page entry,
914  * and a page entry and page directory to the page they refer to.
915  */
916 static inline pte_t mk_pte_phys(unsigned long physpage, pgprot_t pgprot)
917 {
918 	pte_t __pte;
919 	pte_val(__pte) = physpage + pgprot_val(pgprot);
920 	return pte_mkyoung(__pte);
921 }
922 
923 static inline pte_t mk_pte(struct page *page, pgprot_t pgprot)
924 {
925 	unsigned long physpage = page_to_phys(page);
926 	pte_t __pte = mk_pte_phys(physpage, pgprot);
927 
928 	if (pte_write(__pte) && PageDirty(page))
929 		__pte = pte_mkdirty(__pte);
930 	return __pte;
931 }
932 
933 #define pgd_index(address) (((address) >> PGDIR_SHIFT) & (PTRS_PER_PGD-1))
934 #define pud_index(address) (((address) >> PUD_SHIFT) & (PTRS_PER_PUD-1))
935 #define pmd_index(address) (((address) >> PMD_SHIFT) & (PTRS_PER_PMD-1))
936 #define pte_index(address) (((address) >> PAGE_SHIFT) & (PTRS_PER_PTE-1))
937 
938 #define pgd_offset(mm, address) ((mm)->pgd + pgd_index(address))
939 #define pgd_offset_k(address) pgd_offset(&init_mm, address)
940 
941 #define pmd_deref(pmd) (pmd_val(pmd) & _SEGMENT_ENTRY_ORIGIN)
942 #define pud_deref(pud) (pud_val(pud) & _REGION_ENTRY_ORIGIN)
943 #define pgd_deref(pgd) (pgd_val(pgd) & _REGION_ENTRY_ORIGIN)
944 
945 static inline pud_t *pud_offset(pgd_t *pgd, unsigned long address)
946 {
947 	pud_t *pud = (pud_t *) pgd;
948 	if ((pgd_val(*pgd) & _REGION_ENTRY_TYPE_MASK) == _REGION_ENTRY_TYPE_R2)
949 		pud = (pud_t *) pgd_deref(*pgd);
950 	return pud  + pud_index(address);
951 }
952 
953 static inline pmd_t *pmd_offset(pud_t *pud, unsigned long address)
954 {
955 	pmd_t *pmd = (pmd_t *) pud;
956 	if ((pud_val(*pud) & _REGION_ENTRY_TYPE_MASK) == _REGION_ENTRY_TYPE_R3)
957 		pmd = (pmd_t *) pud_deref(*pud);
958 	return pmd + pmd_index(address);
959 }
960 
961 #define pfn_pte(pfn,pgprot) mk_pte_phys(__pa((pfn) << PAGE_SHIFT),(pgprot))
962 #define pte_pfn(x) (pte_val(x) >> PAGE_SHIFT)
963 #define pte_page(x) pfn_to_page(pte_pfn(x))
964 
965 #define pmd_page(pmd) pfn_to_page(pmd_pfn(pmd))
966 
967 /* Find an entry in the lowest level page table.. */
968 #define pte_offset(pmd, addr) ((pte_t *) pmd_deref(*(pmd)) + pte_index(addr))
969 #define pte_offset_kernel(pmd, address) pte_offset(pmd,address)
970 #define pte_offset_map(pmd, address) pte_offset_kernel(pmd, address)
971 #define pte_unmap(pte) do { } while (0)
972 
973 #if defined(CONFIG_TRANSPARENT_HUGEPAGE) || defined(CONFIG_HUGETLB_PAGE)
974 static inline unsigned long massage_pgprot_pmd(pgprot_t pgprot)
975 {
976 	/*
977 	 * pgprot is PAGE_NONE, PAGE_READ, or PAGE_WRITE (see __Pxxx / __Sxxx)
978 	 * Convert to segment table entry format.
979 	 */
980 	if (pgprot_val(pgprot) == pgprot_val(PAGE_NONE))
981 		return pgprot_val(SEGMENT_NONE);
982 	if (pgprot_val(pgprot) == pgprot_val(PAGE_READ))
983 		return pgprot_val(SEGMENT_READ);
984 	return pgprot_val(SEGMENT_WRITE);
985 }
986 
987 static inline pmd_t pmd_wrprotect(pmd_t pmd)
988 {
989 	pmd_val(pmd) &= ~_SEGMENT_ENTRY_WRITE;
990 	pmd_val(pmd) |= _SEGMENT_ENTRY_PROTECT;
991 	return pmd;
992 }
993 
994 static inline pmd_t pmd_mkwrite(pmd_t pmd)
995 {
996 	pmd_val(pmd) |= _SEGMENT_ENTRY_WRITE;
997 	if (pmd_large(pmd) && !(pmd_val(pmd) & _SEGMENT_ENTRY_DIRTY))
998 		return pmd;
999 	pmd_val(pmd) &= ~_SEGMENT_ENTRY_PROTECT;
1000 	return pmd;
1001 }
1002 
1003 static inline pmd_t pmd_mkclean(pmd_t pmd)
1004 {
1005 	if (pmd_large(pmd)) {
1006 		pmd_val(pmd) &= ~_SEGMENT_ENTRY_DIRTY;
1007 		pmd_val(pmd) |= _SEGMENT_ENTRY_PROTECT;
1008 	}
1009 	return pmd;
1010 }
1011 
1012 static inline pmd_t pmd_mkdirty(pmd_t pmd)
1013 {
1014 	if (pmd_large(pmd)) {
1015 		pmd_val(pmd) |= _SEGMENT_ENTRY_DIRTY |
1016 				_SEGMENT_ENTRY_SOFT_DIRTY;
1017 		if (pmd_val(pmd) & _SEGMENT_ENTRY_WRITE)
1018 			pmd_val(pmd) &= ~_SEGMENT_ENTRY_PROTECT;
1019 	}
1020 	return pmd;
1021 }
1022 
1023 static inline pmd_t pmd_mkyoung(pmd_t pmd)
1024 {
1025 	if (pmd_large(pmd)) {
1026 		pmd_val(pmd) |= _SEGMENT_ENTRY_YOUNG;
1027 		if (pmd_val(pmd) & _SEGMENT_ENTRY_READ)
1028 			pmd_val(pmd) &= ~_SEGMENT_ENTRY_INVALID;
1029 	}
1030 	return pmd;
1031 }
1032 
1033 static inline pmd_t pmd_mkold(pmd_t pmd)
1034 {
1035 	if (pmd_large(pmd)) {
1036 		pmd_val(pmd) &= ~_SEGMENT_ENTRY_YOUNG;
1037 		pmd_val(pmd) |= _SEGMENT_ENTRY_INVALID;
1038 	}
1039 	return pmd;
1040 }
1041 
1042 static inline pmd_t pmd_modify(pmd_t pmd, pgprot_t newprot)
1043 {
1044 	if (pmd_large(pmd)) {
1045 		pmd_val(pmd) &= _SEGMENT_ENTRY_ORIGIN_LARGE |
1046 			_SEGMENT_ENTRY_DIRTY | _SEGMENT_ENTRY_YOUNG |
1047 			_SEGMENT_ENTRY_LARGE | _SEGMENT_ENTRY_SOFT_DIRTY;
1048 		pmd_val(pmd) |= massage_pgprot_pmd(newprot);
1049 		if (!(pmd_val(pmd) & _SEGMENT_ENTRY_DIRTY))
1050 			pmd_val(pmd) |= _SEGMENT_ENTRY_PROTECT;
1051 		if (!(pmd_val(pmd) & _SEGMENT_ENTRY_YOUNG))
1052 			pmd_val(pmd) |= _SEGMENT_ENTRY_INVALID;
1053 		return pmd;
1054 	}
1055 	pmd_val(pmd) &= _SEGMENT_ENTRY_ORIGIN;
1056 	pmd_val(pmd) |= massage_pgprot_pmd(newprot);
1057 	return pmd;
1058 }
1059 
1060 static inline pmd_t mk_pmd_phys(unsigned long physpage, pgprot_t pgprot)
1061 {
1062 	pmd_t __pmd;
1063 	pmd_val(__pmd) = physpage + massage_pgprot_pmd(pgprot);
1064 	return __pmd;
1065 }
1066 
1067 #endif /* CONFIG_TRANSPARENT_HUGEPAGE || CONFIG_HUGETLB_PAGE */
1068 
1069 static inline void __pmdp_csp(pmd_t *pmdp)
1070 {
1071 	register unsigned long reg2 asm("2") = pmd_val(*pmdp);
1072 	register unsigned long reg3 asm("3") = pmd_val(*pmdp) |
1073 					       _SEGMENT_ENTRY_INVALID;
1074 	register unsigned long reg4 asm("4") = ((unsigned long) pmdp) + 5;
1075 
1076 	asm volatile(
1077 		"	csp %1,%3"
1078 		: "=m" (*pmdp)
1079 		: "d" (reg2), "d" (reg3), "d" (reg4), "m" (*pmdp) : "cc");
1080 }
1081 
1082 static inline void __pmdp_idte(unsigned long address, pmd_t *pmdp)
1083 {
1084 	unsigned long sto;
1085 
1086 	sto = (unsigned long) pmdp - pmd_index(address) * sizeof(pmd_t);
1087 	asm volatile(
1088 		"	.insn	rrf,0xb98e0000,%2,%3,0,0"
1089 		: "=m" (*pmdp)
1090 		: "m" (*pmdp), "a" (sto), "a" ((address & HPAGE_MASK))
1091 		: "cc" );
1092 }
1093 
1094 static inline void __pmdp_idte_local(unsigned long address, pmd_t *pmdp)
1095 {
1096 	unsigned long sto;
1097 
1098 	sto = (unsigned long) pmdp - pmd_index(address) * sizeof(pmd_t);
1099 	asm volatile(
1100 		"	.insn	rrf,0xb98e0000,%2,%3,0,1"
1101 		: "=m" (*pmdp)
1102 		: "m" (*pmdp), "a" (sto), "a" ((address & HPAGE_MASK))
1103 		: "cc" );
1104 }
1105 
1106 pmd_t pmdp_xchg_direct(struct mm_struct *, unsigned long, pmd_t *, pmd_t);
1107 pmd_t pmdp_xchg_lazy(struct mm_struct *, unsigned long, pmd_t *, pmd_t);
1108 
1109 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
1110 
1111 #define __HAVE_ARCH_PGTABLE_DEPOSIT
1112 void pgtable_trans_huge_deposit(struct mm_struct *mm, pmd_t *pmdp,
1113 				pgtable_t pgtable);
1114 
1115 #define __HAVE_ARCH_PGTABLE_WITHDRAW
1116 pgtable_t pgtable_trans_huge_withdraw(struct mm_struct *mm, pmd_t *pmdp);
1117 
1118 #define  __HAVE_ARCH_PMDP_SET_ACCESS_FLAGS
1119 static inline int pmdp_set_access_flags(struct vm_area_struct *vma,
1120 					unsigned long addr, pmd_t *pmdp,
1121 					pmd_t entry, int dirty)
1122 {
1123 	VM_BUG_ON(addr & ~HPAGE_MASK);
1124 
1125 	entry = pmd_mkyoung(entry);
1126 	if (dirty)
1127 		entry = pmd_mkdirty(entry);
1128 	if (pmd_val(*pmdp) == pmd_val(entry))
1129 		return 0;
1130 	pmdp_xchg_direct(vma->vm_mm, addr, pmdp, entry);
1131 	return 1;
1132 }
1133 
1134 #define __HAVE_ARCH_PMDP_TEST_AND_CLEAR_YOUNG
1135 static inline int pmdp_test_and_clear_young(struct vm_area_struct *vma,
1136 					    unsigned long addr, pmd_t *pmdp)
1137 {
1138 	pmd_t pmd = *pmdp;
1139 
1140 	pmd = pmdp_xchg_direct(vma->vm_mm, addr, pmdp, pmd_mkold(pmd));
1141 	return pmd_young(pmd);
1142 }
1143 
1144 #define __HAVE_ARCH_PMDP_CLEAR_YOUNG_FLUSH
1145 static inline int pmdp_clear_flush_young(struct vm_area_struct *vma,
1146 					 unsigned long addr, pmd_t *pmdp)
1147 {
1148 	VM_BUG_ON(addr & ~HPAGE_MASK);
1149 	return pmdp_test_and_clear_young(vma, addr, pmdp);
1150 }
1151 
1152 static inline void set_pmd_at(struct mm_struct *mm, unsigned long addr,
1153 			      pmd_t *pmdp, pmd_t entry)
1154 {
1155 	*pmdp = entry;
1156 }
1157 
1158 static inline pmd_t pmd_mkhuge(pmd_t pmd)
1159 {
1160 	pmd_val(pmd) |= _SEGMENT_ENTRY_LARGE;
1161 	pmd_val(pmd) |= _SEGMENT_ENTRY_YOUNG;
1162 	pmd_val(pmd) |= _SEGMENT_ENTRY_PROTECT;
1163 	return pmd;
1164 }
1165 
1166 #define __HAVE_ARCH_PMDP_HUGE_GET_AND_CLEAR
1167 static inline pmd_t pmdp_huge_get_and_clear(struct mm_struct *mm,
1168 					    unsigned long addr, pmd_t *pmdp)
1169 {
1170 	return pmdp_xchg_direct(mm, addr, pmdp, __pmd(_SEGMENT_ENTRY_INVALID));
1171 }
1172 
1173 #define __HAVE_ARCH_PMDP_HUGE_GET_AND_CLEAR_FULL
1174 static inline pmd_t pmdp_huge_get_and_clear_full(struct mm_struct *mm,
1175 						 unsigned long addr,
1176 						 pmd_t *pmdp, int full)
1177 {
1178 	if (full) {
1179 		pmd_t pmd = *pmdp;
1180 		*pmdp = __pmd(_SEGMENT_ENTRY_INVALID);
1181 		return pmd;
1182 	}
1183 	return pmdp_xchg_lazy(mm, addr, pmdp, __pmd(_SEGMENT_ENTRY_INVALID));
1184 }
1185 
1186 #define __HAVE_ARCH_PMDP_HUGE_CLEAR_FLUSH
1187 static inline pmd_t pmdp_huge_clear_flush(struct vm_area_struct *vma,
1188 					  unsigned long addr, pmd_t *pmdp)
1189 {
1190 	return pmdp_huge_get_and_clear(vma->vm_mm, addr, pmdp);
1191 }
1192 
1193 #define __HAVE_ARCH_PMDP_INVALIDATE
1194 static inline void pmdp_invalidate(struct vm_area_struct *vma,
1195 				   unsigned long addr, pmd_t *pmdp)
1196 {
1197 	pmdp_xchg_direct(vma->vm_mm, addr, pmdp, __pmd(_SEGMENT_ENTRY_INVALID));
1198 }
1199 
1200 #define __HAVE_ARCH_PMDP_SET_WRPROTECT
1201 static inline void pmdp_set_wrprotect(struct mm_struct *mm,
1202 				      unsigned long addr, pmd_t *pmdp)
1203 {
1204 	pmd_t pmd = *pmdp;
1205 
1206 	if (pmd_write(pmd))
1207 		pmd = pmdp_xchg_lazy(mm, addr, pmdp, pmd_wrprotect(pmd));
1208 }
1209 
1210 static inline pmd_t pmdp_collapse_flush(struct vm_area_struct *vma,
1211 					unsigned long address,
1212 					pmd_t *pmdp)
1213 {
1214 	return pmdp_huge_get_and_clear(vma->vm_mm, address, pmdp);
1215 }
1216 #define pmdp_collapse_flush pmdp_collapse_flush
1217 
1218 #define pfn_pmd(pfn, pgprot)	mk_pmd_phys(__pa((pfn) << PAGE_SHIFT), (pgprot))
1219 #define mk_pmd(page, pgprot)	pfn_pmd(page_to_pfn(page), (pgprot))
1220 
1221 static inline int pmd_trans_huge(pmd_t pmd)
1222 {
1223 	return pmd_val(pmd) & _SEGMENT_ENTRY_LARGE;
1224 }
1225 
1226 #define has_transparent_hugepage has_transparent_hugepage
1227 static inline int has_transparent_hugepage(void)
1228 {
1229 	return MACHINE_HAS_HPAGE ? 1 : 0;
1230 }
1231 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
1232 
1233 /*
1234  * 64 bit swap entry format:
1235  * A page-table entry has some bits we have to treat in a special way.
1236  * Bits 52 and bit 55 have to be zero, otherwise a specification
1237  * exception will occur instead of a page translation exception. The
1238  * specification exception has the bad habit not to store necessary
1239  * information in the lowcore.
1240  * Bits 54 and 63 are used to indicate the page type.
1241  * A swap pte is indicated by bit pattern (pte & 0x201) == 0x200
1242  * This leaves the bits 0-51 and bits 56-62 to store type and offset.
1243  * We use the 5 bits from 57-61 for the type and the 52 bits from 0-51
1244  * for the offset.
1245  * |			  offset			|01100|type |00|
1246  * |0000000000111111111122222222223333333333444444444455|55555|55566|66|
1247  * |0123456789012345678901234567890123456789012345678901|23456|78901|23|
1248  */
1249 
1250 #define __SWP_OFFSET_MASK	((1UL << 52) - 1)
1251 #define __SWP_OFFSET_SHIFT	12
1252 #define __SWP_TYPE_MASK		((1UL << 5) - 1)
1253 #define __SWP_TYPE_SHIFT	2
1254 
1255 static inline pte_t mk_swap_pte(unsigned long type, unsigned long offset)
1256 {
1257 	pte_t pte;
1258 
1259 	pte_val(pte) = _PAGE_INVALID | _PAGE_PROTECT;
1260 	pte_val(pte) |= (offset & __SWP_OFFSET_MASK) << __SWP_OFFSET_SHIFT;
1261 	pte_val(pte) |= (type & __SWP_TYPE_MASK) << __SWP_TYPE_SHIFT;
1262 	return pte;
1263 }
1264 
1265 static inline unsigned long __swp_type(swp_entry_t entry)
1266 {
1267 	return (entry.val >> __SWP_TYPE_SHIFT) & __SWP_TYPE_MASK;
1268 }
1269 
1270 static inline unsigned long __swp_offset(swp_entry_t entry)
1271 {
1272 	return (entry.val >> __SWP_OFFSET_SHIFT) & __SWP_OFFSET_MASK;
1273 }
1274 
1275 static inline swp_entry_t __swp_entry(unsigned long type, unsigned long offset)
1276 {
1277 	return (swp_entry_t) { pte_val(mk_swap_pte(type, offset)) };
1278 }
1279 
1280 #define __pte_to_swp_entry(pte)	((swp_entry_t) { pte_val(pte) })
1281 #define __swp_entry_to_pte(x)	((pte_t) { (x).val })
1282 
1283 #endif /* !__ASSEMBLY__ */
1284 
1285 #define kern_addr_valid(addr)   (1)
1286 
1287 extern int vmem_add_mapping(unsigned long start, unsigned long size);
1288 extern int vmem_remove_mapping(unsigned long start, unsigned long size);
1289 extern int s390_enable_sie(void);
1290 extern int s390_enable_skey(void);
1291 extern void s390_reset_cmma(struct mm_struct *mm);
1292 
1293 /* s390 has a private copy of get unmapped area to deal with cache synonyms */
1294 #define HAVE_ARCH_UNMAPPED_AREA
1295 #define HAVE_ARCH_UNMAPPED_AREA_TOPDOWN
1296 
1297 /*
1298  * No page table caches to initialise
1299  */
1300 static inline void pgtable_cache_init(void) { }
1301 static inline void check_pgt_cache(void) { }
1302 
1303 #include <asm-generic/pgtable.h>
1304 
1305 #endif /* _S390_PAGE_H */
1306