1 #ifndef _ASM_POWERPC_MMU_HASH64_H_
2 #define _ASM_POWERPC_MMU_HASH64_H_
3 /*
4  * PowerPC64 memory management structures
5  *
6  * Dave Engebretsen & Mike Corrigan <{engebret|mikejc}@us.ibm.com>
7  *   PPC64 rework.
8  *
9  * This program is free software; you can redistribute it and/or
10  * modify it under the terms of the GNU General Public License
11  * as published by the Free Software Foundation; either version
12  * 2 of the License, or (at your option) any later version.
13  */
14 
15 #include <asm/asm-compat.h>
16 #include <asm/page.h>
17 #include <asm/bug.h>
18 
19 /*
20  * This is necessary to get the definition of PGTABLE_RANGE which we
21  * need for various slices related matters. Note that this isn't the
22  * complete pgtable.h but only a portion of it.
23  */
24 #include <asm/book3s/64/pgtable.h>
25 #include <asm/bug.h>
26 #include <asm/processor.h>
27 
28 /*
29  * SLB
30  */
31 
32 #define SLB_NUM_BOLTED		3
33 #define SLB_CACHE_ENTRIES	8
34 #define SLB_MIN_SIZE		32
35 
36 /* Bits in the SLB ESID word */
37 #define SLB_ESID_V		ASM_CONST(0x0000000008000000) /* valid */
38 
39 /* Bits in the SLB VSID word */
40 #define SLB_VSID_SHIFT		12
41 #define SLB_VSID_SHIFT_1T	24
42 #define SLB_VSID_SSIZE_SHIFT	62
43 #define SLB_VSID_B		ASM_CONST(0xc000000000000000)
44 #define SLB_VSID_B_256M		ASM_CONST(0x0000000000000000)
45 #define SLB_VSID_B_1T		ASM_CONST(0x4000000000000000)
46 #define SLB_VSID_KS		ASM_CONST(0x0000000000000800)
47 #define SLB_VSID_KP		ASM_CONST(0x0000000000000400)
48 #define SLB_VSID_N		ASM_CONST(0x0000000000000200) /* no-execute */
49 #define SLB_VSID_L		ASM_CONST(0x0000000000000100)
50 #define SLB_VSID_C		ASM_CONST(0x0000000000000080) /* class */
51 #define SLB_VSID_LP		ASM_CONST(0x0000000000000030)
52 #define SLB_VSID_LP_00		ASM_CONST(0x0000000000000000)
53 #define SLB_VSID_LP_01		ASM_CONST(0x0000000000000010)
54 #define SLB_VSID_LP_10		ASM_CONST(0x0000000000000020)
55 #define SLB_VSID_LP_11		ASM_CONST(0x0000000000000030)
56 #define SLB_VSID_LLP		(SLB_VSID_L|SLB_VSID_LP)
57 
58 #define SLB_VSID_KERNEL		(SLB_VSID_KP)
59 #define SLB_VSID_USER		(SLB_VSID_KP|SLB_VSID_KS|SLB_VSID_C)
60 
61 #define SLBIE_C			(0x08000000)
62 #define SLBIE_SSIZE_SHIFT	25
63 
64 /*
65  * Hash table
66  */
67 
68 #define HPTES_PER_GROUP 8
69 
70 #define HPTE_V_SSIZE_SHIFT	62
71 #define HPTE_V_AVPN_SHIFT	7
72 #define HPTE_V_AVPN		ASM_CONST(0x3fffffffffffff80)
73 #define HPTE_V_AVPN_VAL(x)	(((x) & HPTE_V_AVPN) >> HPTE_V_AVPN_SHIFT)
74 #define HPTE_V_COMPARE(x,y)	(!(((x) ^ (y)) & 0xffffffffffffff80UL))
75 #define HPTE_V_BOLTED		ASM_CONST(0x0000000000000010)
76 #define HPTE_V_LOCK		ASM_CONST(0x0000000000000008)
77 #define HPTE_V_LARGE		ASM_CONST(0x0000000000000004)
78 #define HPTE_V_SECONDARY	ASM_CONST(0x0000000000000002)
79 #define HPTE_V_VALID		ASM_CONST(0x0000000000000001)
80 
81 #define HPTE_R_PP0		ASM_CONST(0x8000000000000000)
82 #define HPTE_R_TS		ASM_CONST(0x4000000000000000)
83 #define HPTE_R_KEY_HI		ASM_CONST(0x3000000000000000)
84 #define HPTE_R_RPN_SHIFT	12
85 #define HPTE_R_RPN		ASM_CONST(0x0ffffffffffff000)
86 #define HPTE_R_PP		ASM_CONST(0x0000000000000003)
87 #define HPTE_R_N		ASM_CONST(0x0000000000000004)
88 #define HPTE_R_G		ASM_CONST(0x0000000000000008)
89 #define HPTE_R_M		ASM_CONST(0x0000000000000010)
90 #define HPTE_R_I		ASM_CONST(0x0000000000000020)
91 #define HPTE_R_W		ASM_CONST(0x0000000000000040)
92 #define HPTE_R_WIMG		ASM_CONST(0x0000000000000078)
93 #define HPTE_R_C		ASM_CONST(0x0000000000000080)
94 #define HPTE_R_R		ASM_CONST(0x0000000000000100)
95 #define HPTE_R_KEY_LO		ASM_CONST(0x0000000000000e00)
96 
97 #define HPTE_V_1TB_SEG		ASM_CONST(0x4000000000000000)
98 #define HPTE_V_VRMA_MASK	ASM_CONST(0x4001ffffff000000)
99 
100 /* Values for PP (assumes Ks=0, Kp=1) */
101 #define PP_RWXX	0	/* Supervisor read/write, User none */
102 #define PP_RWRX 1	/* Supervisor read/write, User read */
103 #define PP_RWRW 2	/* Supervisor read/write, User read/write */
104 #define PP_RXRX 3	/* Supervisor read,       User read */
105 #define PP_RXXX	(HPTE_R_PP0 | 2)	/* Supervisor read, user none */
106 
107 /* Fields for tlbiel instruction in architecture 2.06 */
108 #define TLBIEL_INVAL_SEL_MASK	0xc00	/* invalidation selector */
109 #define  TLBIEL_INVAL_PAGE	0x000	/* invalidate a single page */
110 #define  TLBIEL_INVAL_SET_LPID	0x800	/* invalidate a set for current LPID */
111 #define  TLBIEL_INVAL_SET	0xc00	/* invalidate a set for all LPIDs */
112 #define TLBIEL_INVAL_SET_MASK	0xfff000	/* set number to inval. */
113 #define TLBIEL_INVAL_SET_SHIFT	12
114 
115 #define POWER7_TLB_SETS		128	/* # sets in POWER7 TLB */
116 #define POWER8_TLB_SETS		512	/* # sets in POWER8 TLB */
117 #define POWER9_TLB_SETS_HASH	256	/* # sets in POWER9 TLB Hash mode */
118 
119 #ifndef __ASSEMBLY__
120 
121 struct hash_pte {
122 	__be64 v;
123 	__be64 r;
124 };
125 
126 extern struct hash_pte *htab_address;
127 extern unsigned long htab_size_bytes;
128 extern unsigned long htab_hash_mask;
129 
130 /*
131  * Page size definition
132  *
133  *    shift : is the "PAGE_SHIFT" value for that page size
134  *    sllp  : is a bit mask with the value of SLB L || LP to be or'ed
135  *            directly to a slbmte "vsid" value
136  *    penc  : is the HPTE encoding mask for the "LP" field:
137  *
138  */
139 struct mmu_psize_def
140 {
141 	unsigned int	shift;	/* number of bits */
142 	int		penc[MMU_PAGE_COUNT];	/* HPTE encoding */
143 	unsigned int	tlbiel;	/* tlbiel supported for that page size */
144 	unsigned long	avpnm;	/* bits to mask out in AVPN in the HPTE */
145 	unsigned long	sllp;	/* SLB L||LP (exact mask to use in slbmte) */
146 };
147 extern struct mmu_psize_def mmu_psize_defs[MMU_PAGE_COUNT];
148 
149 static inline int shift_to_mmu_psize(unsigned int shift)
150 {
151 	int psize;
152 
153 	for (psize = 0; psize < MMU_PAGE_COUNT; ++psize)
154 		if (mmu_psize_defs[psize].shift == shift)
155 			return psize;
156 	return -1;
157 }
158 
159 static inline unsigned int mmu_psize_to_shift(unsigned int mmu_psize)
160 {
161 	if (mmu_psize_defs[mmu_psize].shift)
162 		return mmu_psize_defs[mmu_psize].shift;
163 	BUG();
164 }
165 
166 #endif /* __ASSEMBLY__ */
167 
168 /*
169  * Segment sizes.
170  * These are the values used by hardware in the B field of
171  * SLB entries and the first dword of MMU hashtable entries.
172  * The B field is 2 bits; the values 2 and 3 are unused and reserved.
173  */
174 #define MMU_SEGSIZE_256M	0
175 #define MMU_SEGSIZE_1T		1
176 
177 /*
178  * encode page number shift.
179  * in order to fit the 78 bit va in a 64 bit variable we shift the va by
180  * 12 bits. This enable us to address upto 76 bit va.
181  * For hpt hash from a va we can ignore the page size bits of va and for
182  * hpte encoding we ignore up to 23 bits of va. So ignoring lower 12 bits ensure
183  * we work in all cases including 4k page size.
184  */
185 #define VPN_SHIFT	12
186 
187 /*
188  * HPTE Large Page (LP) details
189  */
190 #define LP_SHIFT	12
191 #define LP_BITS		8
192 #define LP_MASK(i)	((0xFF >> (i)) << LP_SHIFT)
193 
194 #ifndef __ASSEMBLY__
195 
196 static inline int slb_vsid_shift(int ssize)
197 {
198 	if (ssize == MMU_SEGSIZE_256M)
199 		return SLB_VSID_SHIFT;
200 	return SLB_VSID_SHIFT_1T;
201 }
202 
203 static inline int segment_shift(int ssize)
204 {
205 	if (ssize == MMU_SEGSIZE_256M)
206 		return SID_SHIFT;
207 	return SID_SHIFT_1T;
208 }
209 
210 /*
211  * The current system page and segment sizes
212  */
213 extern int mmu_linear_psize;
214 extern int mmu_virtual_psize;
215 extern int mmu_vmalloc_psize;
216 extern int mmu_vmemmap_psize;
217 extern int mmu_io_psize;
218 extern int mmu_kernel_ssize;
219 extern int mmu_highuser_ssize;
220 extern u16 mmu_slb_size;
221 extern unsigned long tce_alloc_start, tce_alloc_end;
222 
223 /*
224  * If the processor supports 64k normal pages but not 64k cache
225  * inhibited pages, we have to be prepared to switch processes
226  * to use 4k pages when they create cache-inhibited mappings.
227  * If this is the case, mmu_ci_restrictions will be set to 1.
228  */
229 extern int mmu_ci_restrictions;
230 
231 /*
232  * This computes the AVPN and B fields of the first dword of a HPTE,
233  * for use when we want to match an existing PTE.  The bottom 7 bits
234  * of the returned value are zero.
235  */
236 static inline unsigned long hpte_encode_avpn(unsigned long vpn, int psize,
237 					     int ssize)
238 {
239 	unsigned long v;
240 	/*
241 	 * The AVA field omits the low-order 23 bits of the 78 bits VA.
242 	 * These bits are not needed in the PTE, because the
243 	 * low-order b of these bits are part of the byte offset
244 	 * into the virtual page and, if b < 23, the high-order
245 	 * 23-b of these bits are always used in selecting the
246 	 * PTEGs to be searched
247 	 */
248 	v = (vpn >> (23 - VPN_SHIFT)) & ~(mmu_psize_defs[psize].avpnm);
249 	v <<= HPTE_V_AVPN_SHIFT;
250 	v |= ((unsigned long) ssize) << HPTE_V_SSIZE_SHIFT;
251 	return v;
252 }
253 
254 /*
255  * This function sets the AVPN and L fields of the HPTE  appropriately
256  * using the base page size and actual page size.
257  */
258 static inline unsigned long hpte_encode_v(unsigned long vpn, int base_psize,
259 					  int actual_psize, int ssize)
260 {
261 	unsigned long v;
262 	v = hpte_encode_avpn(vpn, base_psize, ssize);
263 	if (actual_psize != MMU_PAGE_4K)
264 		v |= HPTE_V_LARGE;
265 	return v;
266 }
267 
268 /*
269  * This function sets the ARPN, and LP fields of the HPTE appropriately
270  * for the page size. We assume the pa is already "clean" that is properly
271  * aligned for the requested page size
272  */
273 static inline unsigned long hpte_encode_r(unsigned long pa, int base_psize,
274 					  int actual_psize)
275 {
276 	/* A 4K page needs no special encoding */
277 	if (actual_psize == MMU_PAGE_4K)
278 		return pa & HPTE_R_RPN;
279 	else {
280 		unsigned int penc = mmu_psize_defs[base_psize].penc[actual_psize];
281 		unsigned int shift = mmu_psize_defs[actual_psize].shift;
282 		return (pa & ~((1ul << shift) - 1)) | (penc << LP_SHIFT);
283 	}
284 }
285 
286 /*
287  * Build a VPN_SHIFT bit shifted va given VSID, EA and segment size.
288  */
289 static inline unsigned long hpt_vpn(unsigned long ea,
290 				    unsigned long vsid, int ssize)
291 {
292 	unsigned long mask;
293 	int s_shift = segment_shift(ssize);
294 
295 	mask = (1ul << (s_shift - VPN_SHIFT)) - 1;
296 	return (vsid << (s_shift - VPN_SHIFT)) | ((ea >> VPN_SHIFT) & mask);
297 }
298 
299 /*
300  * This hashes a virtual address
301  */
302 static inline unsigned long hpt_hash(unsigned long vpn,
303 				     unsigned int shift, int ssize)
304 {
305 	int mask;
306 	unsigned long hash, vsid;
307 
308 	/* VPN_SHIFT can be atmost 12 */
309 	if (ssize == MMU_SEGSIZE_256M) {
310 		mask = (1ul << (SID_SHIFT - VPN_SHIFT)) - 1;
311 		hash = (vpn >> (SID_SHIFT - VPN_SHIFT)) ^
312 			((vpn & mask) >> (shift - VPN_SHIFT));
313 	} else {
314 		mask = (1ul << (SID_SHIFT_1T - VPN_SHIFT)) - 1;
315 		vsid = vpn >> (SID_SHIFT_1T - VPN_SHIFT);
316 		hash = vsid ^ (vsid << 25) ^
317 			((vpn & mask) >> (shift - VPN_SHIFT)) ;
318 	}
319 	return hash & 0x7fffffffffUL;
320 }
321 
322 #define HPTE_LOCAL_UPDATE	0x1
323 #define HPTE_NOHPTE_UPDATE	0x2
324 
325 extern int __hash_page_4K(unsigned long ea, unsigned long access,
326 			  unsigned long vsid, pte_t *ptep, unsigned long trap,
327 			  unsigned long flags, int ssize, int subpage_prot);
328 extern int __hash_page_64K(unsigned long ea, unsigned long access,
329 			   unsigned long vsid, pte_t *ptep, unsigned long trap,
330 			   unsigned long flags, int ssize);
331 struct mm_struct;
332 unsigned int hash_page_do_lazy_icache(unsigned int pp, pte_t pte, int trap);
333 extern int hash_page_mm(struct mm_struct *mm, unsigned long ea,
334 			unsigned long access, unsigned long trap,
335 			unsigned long flags);
336 extern int hash_page(unsigned long ea, unsigned long access, unsigned long trap,
337 		     unsigned long dsisr);
338 int __hash_page_huge(unsigned long ea, unsigned long access, unsigned long vsid,
339 		     pte_t *ptep, unsigned long trap, unsigned long flags,
340 		     int ssize, unsigned int shift, unsigned int mmu_psize);
341 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
342 extern int __hash_page_thp(unsigned long ea, unsigned long access,
343 			   unsigned long vsid, pmd_t *pmdp, unsigned long trap,
344 			   unsigned long flags, int ssize, unsigned int psize);
345 #else
346 static inline int __hash_page_thp(unsigned long ea, unsigned long access,
347 				  unsigned long vsid, pmd_t *pmdp,
348 				  unsigned long trap, unsigned long flags,
349 				  int ssize, unsigned int psize)
350 {
351 	BUG();
352 	return -1;
353 }
354 #endif
355 extern void hash_failure_debug(unsigned long ea, unsigned long access,
356 			       unsigned long vsid, unsigned long trap,
357 			       int ssize, int psize, int lpsize,
358 			       unsigned long pte);
359 extern int htab_bolt_mapping(unsigned long vstart, unsigned long vend,
360 			     unsigned long pstart, unsigned long prot,
361 			     int psize, int ssize);
362 int htab_remove_mapping(unsigned long vstart, unsigned long vend,
363 			int psize, int ssize);
364 extern void add_gpage(u64 addr, u64 page_size, unsigned long number_of_pages);
365 extern void demote_segment_4k(struct mm_struct *mm, unsigned long addr);
366 
367 extern void hpte_init_native(void);
368 extern void hpte_init_lpar(void);
369 extern void hpte_init_beat(void);
370 extern void hpte_init_beat_v3(void);
371 
372 extern void slb_initialize(void);
373 extern void slb_flush_and_rebolt(void);
374 
375 extern void slb_vmalloc_update(void);
376 extern void slb_set_size(u16 size);
377 #endif /* __ASSEMBLY__ */
378 
379 /*
380  * VSID allocation (256MB segment)
381  *
382  * We first generate a 37-bit "proto-VSID". Proto-VSIDs are generated
383  * from mmu context id and effective segment id of the address.
384  *
385  * For user processes max context id is limited to ((1ul << 19) - 5)
386  * for kernel space, we use the top 4 context ids to map address as below
387  * NOTE: each context only support 64TB now.
388  * 0x7fffc -  [ 0xc000000000000000 - 0xc0003fffffffffff ]
389  * 0x7fffd -  [ 0xd000000000000000 - 0xd0003fffffffffff ]
390  * 0x7fffe -  [ 0xe000000000000000 - 0xe0003fffffffffff ]
391  * 0x7ffff -  [ 0xf000000000000000 - 0xf0003fffffffffff ]
392  *
393  * The proto-VSIDs are then scrambled into real VSIDs with the
394  * multiplicative hash:
395  *
396  *	VSID = (proto-VSID * VSID_MULTIPLIER) % VSID_MODULUS
397  *
398  * VSID_MULTIPLIER is prime, so in particular it is
399  * co-prime to VSID_MODULUS, making this a 1:1 scrambling function.
400  * Because the modulus is 2^n-1 we can compute it efficiently without
401  * a divide or extra multiply (see below). The scramble function gives
402  * robust scattering in the hash table (at least based on some initial
403  * results).
404  *
405  * We also consider VSID 0 special. We use VSID 0 for slb entries mapping
406  * bad address. This enables us to consolidate bad address handling in
407  * hash_page.
408  *
409  * We also need to avoid the last segment of the last context, because that
410  * would give a protovsid of 0x1fffffffff. That will result in a VSID 0
411  * because of the modulo operation in vsid scramble. But the vmemmap
412  * (which is what uses region 0xf) will never be close to 64TB in size
413  * (it's 56 bytes per page of system memory).
414  */
415 
416 #define CONTEXT_BITS		19
417 #define ESID_BITS		18
418 #define ESID_BITS_1T		6
419 
420 /*
421  * 256MB segment
422  * The proto-VSID space has 2^(CONTEX_BITS + ESID_BITS) - 1 segments
423  * available for user + kernel mapping. The top 4 contexts are used for
424  * kernel mapping. Each segment contains 2^28 bytes. Each
425  * context maps 2^46 bytes (64TB) so we can support 2^19-1 contexts
426  * (19 == 37 + 28 - 46).
427  */
428 #define MAX_USER_CONTEXT	((ASM_CONST(1) << CONTEXT_BITS) - 5)
429 
430 /*
431  * This should be computed such that protovosid * vsid_mulitplier
432  * doesn't overflow 64 bits. It should also be co-prime to vsid_modulus
433  */
434 #define VSID_MULTIPLIER_256M	ASM_CONST(12538073)	/* 24-bit prime */
435 #define VSID_BITS_256M		(CONTEXT_BITS + ESID_BITS)
436 #define VSID_MODULUS_256M	((1UL<<VSID_BITS_256M)-1)
437 
438 #define VSID_MULTIPLIER_1T	ASM_CONST(12538073)	/* 24-bit prime */
439 #define VSID_BITS_1T		(CONTEXT_BITS + ESID_BITS_1T)
440 #define VSID_MODULUS_1T		((1UL<<VSID_BITS_1T)-1)
441 
442 
443 #define USER_VSID_RANGE	(1UL << (ESID_BITS + SID_SHIFT))
444 
445 /*
446  * This macro generates asm code to compute the VSID scramble
447  * function.  Used in slb_allocate() and do_stab_bolted.  The function
448  * computed is: (protovsid*VSID_MULTIPLIER) % VSID_MODULUS
449  *
450  *	rt = register continaing the proto-VSID and into which the
451  *		VSID will be stored
452  *	rx = scratch register (clobbered)
453  *
454  * 	- rt and rx must be different registers
455  * 	- The answer will end up in the low VSID_BITS bits of rt.  The higher
456  * 	  bits may contain other garbage, so you may need to mask the
457  * 	  result.
458  */
459 #define ASM_VSID_SCRAMBLE(rt, rx, size)					\
460 	lis	rx,VSID_MULTIPLIER_##size@h;				\
461 	ori	rx,rx,VSID_MULTIPLIER_##size@l;				\
462 	mulld	rt,rt,rx;		/* rt = rt * MULTIPLIER */	\
463 									\
464 	srdi	rx,rt,VSID_BITS_##size;					\
465 	clrldi	rt,rt,(64-VSID_BITS_##size);				\
466 	add	rt,rt,rx;		/* add high and low bits */	\
467 	/* NOTE: explanation based on VSID_BITS_##size = 36		\
468 	 * Now, r3 == VSID (mod 2^36-1), and lies between 0 and		\
469 	 * 2^36-1+2^28-1.  That in particular means that if r3 >=	\
470 	 * 2^36-1, then r3+1 has the 2^36 bit set.  So, if r3+1 has	\
471 	 * the bit clear, r3 already has the answer we want, if it	\
472 	 * doesn't, the answer is the low 36 bits of r3+1.  So in all	\
473 	 * cases the answer is the low 36 bits of (r3 + ((r3+1) >> 36))*/\
474 	addi	rx,rt,1;						\
475 	srdi	rx,rx,VSID_BITS_##size;	/* extract 2^VSID_BITS bit */	\
476 	add	rt,rt,rx
477 
478 /* 4 bits per slice and we have one slice per 1TB */
479 #define SLICE_ARRAY_SIZE  (PGTABLE_RANGE >> 41)
480 
481 #ifndef __ASSEMBLY__
482 
483 #ifdef CONFIG_PPC_SUBPAGE_PROT
484 /*
485  * For the sub-page protection option, we extend the PGD with one of
486  * these.  Basically we have a 3-level tree, with the top level being
487  * the protptrs array.  To optimize speed and memory consumption when
488  * only addresses < 4GB are being protected, pointers to the first
489  * four pages of sub-page protection words are stored in the low_prot
490  * array.
491  * Each page of sub-page protection words protects 1GB (4 bytes
492  * protects 64k).  For the 3-level tree, each page of pointers then
493  * protects 8TB.
494  */
495 struct subpage_prot_table {
496 	unsigned long maxaddr;	/* only addresses < this are protected */
497 	unsigned int **protptrs[(TASK_SIZE_USER64 >> 43)];
498 	unsigned int *low_prot[4];
499 };
500 
501 #define SBP_L1_BITS		(PAGE_SHIFT - 2)
502 #define SBP_L2_BITS		(PAGE_SHIFT - 3)
503 #define SBP_L1_COUNT		(1 << SBP_L1_BITS)
504 #define SBP_L2_COUNT		(1 << SBP_L2_BITS)
505 #define SBP_L2_SHIFT		(PAGE_SHIFT + SBP_L1_BITS)
506 #define SBP_L3_SHIFT		(SBP_L2_SHIFT + SBP_L2_BITS)
507 
508 extern void subpage_prot_free(struct mm_struct *mm);
509 extern void subpage_prot_init_new_context(struct mm_struct *mm);
510 #else
511 static inline void subpage_prot_free(struct mm_struct *mm) {}
512 static inline void subpage_prot_init_new_context(struct mm_struct *mm) { }
513 #endif /* CONFIG_PPC_SUBPAGE_PROT */
514 
515 typedef unsigned long mm_context_id_t;
516 struct spinlock;
517 
518 typedef struct {
519 	mm_context_id_t id;
520 	u16 user_psize;		/* page size index */
521 
522 #ifdef CONFIG_PPC_MM_SLICES
523 	u64 low_slices_psize;	/* SLB page size encodings */
524 	unsigned char high_slices_psize[SLICE_ARRAY_SIZE];
525 #else
526 	u16 sllp;		/* SLB page size encoding */
527 #endif
528 	unsigned long vdso_base;
529 #ifdef CONFIG_PPC_SUBPAGE_PROT
530 	struct subpage_prot_table spt;
531 #endif /* CONFIG_PPC_SUBPAGE_PROT */
532 #ifdef CONFIG_PPC_ICSWX
533 	struct spinlock *cop_lockp; /* guard acop and cop_pid */
534 	unsigned long acop;	/* mask of enabled coprocessor types */
535 	unsigned int cop_pid;	/* pid value used with coprocessors */
536 #endif /* CONFIG_PPC_ICSWX */
537 #ifdef CONFIG_PPC_64K_PAGES
538 	/* for 4K PTE fragment support */
539 	void *pte_frag;
540 #endif
541 #ifdef CONFIG_SPAPR_TCE_IOMMU
542 	struct list_head iommu_group_mem_list;
543 #endif
544 } mm_context_t;
545 
546 
547 #if 0
548 /*
549  * The code below is equivalent to this function for arguments
550  * < 2^VSID_BITS, which is all this should ever be called
551  * with.  However gcc is not clever enough to compute the
552  * modulus (2^n-1) without a second multiply.
553  */
554 #define vsid_scramble(protovsid, size) \
555 	((((protovsid) * VSID_MULTIPLIER_##size) % VSID_MODULUS_##size))
556 
557 #else /* 1 */
558 #define vsid_scramble(protovsid, size) \
559 	({								 \
560 		unsigned long x;					 \
561 		x = (protovsid) * VSID_MULTIPLIER_##size;		 \
562 		x = (x >> VSID_BITS_##size) + (x & VSID_MODULUS_##size); \
563 		(x + ((x+1) >> VSID_BITS_##size)) & VSID_MODULUS_##size; \
564 	})
565 #endif /* 1 */
566 
567 /* Returns the segment size indicator for a user address */
568 static inline int user_segment_size(unsigned long addr)
569 {
570 	/* Use 1T segments if possible for addresses >= 1T */
571 	if (addr >= (1UL << SID_SHIFT_1T))
572 		return mmu_highuser_ssize;
573 	return MMU_SEGSIZE_256M;
574 }
575 
576 static inline unsigned long get_vsid(unsigned long context, unsigned long ea,
577 				     int ssize)
578 {
579 	/*
580 	 * Bad address. We return VSID 0 for that
581 	 */
582 	if ((ea & ~REGION_MASK) >= PGTABLE_RANGE)
583 		return 0;
584 
585 	if (ssize == MMU_SEGSIZE_256M)
586 		return vsid_scramble((context << ESID_BITS)
587 				     | (ea >> SID_SHIFT), 256M);
588 	return vsid_scramble((context << ESID_BITS_1T)
589 			     | (ea >> SID_SHIFT_1T), 1T);
590 }
591 
592 /*
593  * This is only valid for addresses >= PAGE_OFFSET
594  *
595  * For kernel space, we use the top 4 context ids to map address as below
596  * 0x7fffc -  [ 0xc000000000000000 - 0xc0003fffffffffff ]
597  * 0x7fffd -  [ 0xd000000000000000 - 0xd0003fffffffffff ]
598  * 0x7fffe -  [ 0xe000000000000000 - 0xe0003fffffffffff ]
599  * 0x7ffff -  [ 0xf000000000000000 - 0xf0003fffffffffff ]
600  */
601 static inline unsigned long get_kernel_vsid(unsigned long ea, int ssize)
602 {
603 	unsigned long context;
604 
605 	/*
606 	 * kernel take the top 4 context from the available range
607 	 */
608 	context = (MAX_USER_CONTEXT) + ((ea >> 60) - 0xc) + 1;
609 	return get_vsid(context, ea, ssize);
610 }
611 
612 unsigned htab_shift_for_mem_size(unsigned long mem_size);
613 
614 #endif /* __ASSEMBLY__ */
615 
616 #endif /* _ASM_POWERPC_MMU_HASH64_H_ */
617