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1 #ifndef __ASM_SH_PGTABLE_32_H
2 #define __ASM_SH_PGTABLE_32_H
3
4 /*
5 * Linux PTEL encoding.
6 *
7 * Hardware and software bit definitions for the PTEL value (see below for
8 * notes on SH-X2 MMUs and 64-bit PTEs):
9 *
10 * - Bits 0 and 7 are reserved on SH-3 (_PAGE_WT and _PAGE_SZ1 on SH-4).
11 *
12 * - Bit 1 is the SH-bit, but is unused on SH-3 due to an MMU bug (the
13 * hardware PTEL value can't have the SH-bit set when MMUCR.IX is set,
14 * which is the default in cpu-sh3/mmu_context.h:MMU_CONTROL_INIT).
15 *
16 * In order to keep this relatively clean, do not use these for defining
17 * SH-3 specific flags until all of the other unused bits have been
18 * exhausted.
19 *
20 * - Bit 9 is reserved by everyone and used by _PAGE_PROTNONE.
21 *
22 * - Bits 10 and 11 are low bits of the PPN that are reserved on >= 4K pages.
23 * Bit 10 is used for _PAGE_ACCESSED, and bit 11 is used for _PAGE_SPECIAL.
24 *
25 * - On 29 bit platforms, bits 31 to 29 are used for the space attributes
26 * and timing control which (together with bit 0) are moved into the
27 * old-style PTEA on the parts that support it.
28 *
29 * SH-X2 MMUs and extended PTEs
30 *
31 * SH-X2 supports an extended mode TLB with split data arrays due to the
32 * number of bits needed for PR and SZ (now EPR and ESZ) encodings. The PR and
33 * SZ bit placeholders still exist in data array 1, but are implemented as
34 * reserved bits, with the real logic existing in data array 2.
35 *
36 * The downside to this is that we can no longer fit everything in to a 32-bit
37 * PTE encoding, so a 64-bit pte_t is necessary for these parts. On the plus
38 * side, this gives us quite a few spare bits to play with for future usage.
39 */
40 /* Legacy and compat mode bits */
41 #define _PAGE_WT 0x001 /* WT-bit on SH-4, 0 on SH-3 */
42 #define _PAGE_HW_SHARED 0x002 /* SH-bit : shared among processes */
43 #define _PAGE_DIRTY 0x004 /* D-bit : page changed */
44 #define _PAGE_CACHABLE 0x008 /* C-bit : cachable */
45 #define _PAGE_SZ0 0x010 /* SZ0-bit : Size of page */
46 #define _PAGE_RW 0x020 /* PR0-bit : write access allowed */
47 #define _PAGE_USER 0x040 /* PR1-bit : user space access allowed*/
48 #define _PAGE_SZ1 0x080 /* SZ1-bit : Size of page (on SH-4) */
49 #define _PAGE_PRESENT 0x100 /* V-bit : page is valid */
50 #define _PAGE_PROTNONE 0x200 /* software: if not present */
51 #define _PAGE_ACCESSED 0x400 /* software: page referenced */
52 #define _PAGE_SPECIAL 0x800 /* software: special page */
53
54 #define _PAGE_SZ_MASK (_PAGE_SZ0 | _PAGE_SZ1)
55 #define _PAGE_PR_MASK (_PAGE_RW | _PAGE_USER)
56
57 /* Extended mode bits */
58 #define _PAGE_EXT_ESZ0 0x0010 /* ESZ0-bit: Size of page */
59 #define _PAGE_EXT_ESZ1 0x0020 /* ESZ1-bit: Size of page */
60 #define _PAGE_EXT_ESZ2 0x0040 /* ESZ2-bit: Size of page */
61 #define _PAGE_EXT_ESZ3 0x0080 /* ESZ3-bit: Size of page */
62
63 #define _PAGE_EXT_USER_EXEC 0x0100 /* EPR0-bit: User space executable */
64 #define _PAGE_EXT_USER_WRITE 0x0200 /* EPR1-bit: User space writable */
65 #define _PAGE_EXT_USER_READ 0x0400 /* EPR2-bit: User space readable */
66
67 #define _PAGE_EXT_KERN_EXEC 0x0800 /* EPR3-bit: Kernel space executable */
68 #define _PAGE_EXT_KERN_WRITE 0x1000 /* EPR4-bit: Kernel space writable */
69 #define _PAGE_EXT_KERN_READ 0x2000 /* EPR5-bit: Kernel space readable */
70
71 #define _PAGE_EXT_WIRED 0x4000 /* software: Wire TLB entry */
72
73 /* Wrapper for extended mode pgprot twiddling */
74 #define _PAGE_EXT(x) ((unsigned long long)(x) << 32)
75
76 #ifdef CONFIG_X2TLB
77 #define _PAGE_PCC_MASK 0x00000000 /* No legacy PTEA support */
78 #else
79
80 /* software: moves to PTEA.TC (Timing Control) */
81 #define _PAGE_PCC_AREA5 0x00000000 /* use BSC registers for area5 */
82 #define _PAGE_PCC_AREA6 0x80000000 /* use BSC registers for area6 */
83
84 /* software: moves to PTEA.SA[2:0] (Space Attributes) */
85 #define _PAGE_PCC_IODYN 0x00000001 /* IO space, dynamically sized bus */
86 #define _PAGE_PCC_IO8 0x20000000 /* IO space, 8 bit bus */
87 #define _PAGE_PCC_IO16 0x20000001 /* IO space, 16 bit bus */
88 #define _PAGE_PCC_COM8 0x40000000 /* Common Memory space, 8 bit bus */
89 #define _PAGE_PCC_COM16 0x40000001 /* Common Memory space, 16 bit bus */
90 #define _PAGE_PCC_ATR8 0x60000000 /* Attribute Memory space, 8 bit bus */
91 #define _PAGE_PCC_ATR16 0x60000001 /* Attribute Memory space, 6 bit bus */
92
93 #define _PAGE_PCC_MASK 0xe0000001
94
95 /* copy the ptea attributes */
96 static inline unsigned long copy_ptea_attributes(unsigned long x)
97 {
98 return ((x >> 28) & 0xe) | (x & 0x1);
99 }
100 #endif
101
102 /* Mask which drops unused bits from the PTEL value */
103 #if defined(CONFIG_CPU_SH3)
104 #define _PAGE_CLEAR_FLAGS (_PAGE_PROTNONE | _PAGE_ACCESSED| \
105 _PAGE_SZ1 | _PAGE_HW_SHARED)
106 #elif defined(CONFIG_X2TLB)
107 /* Get rid of the legacy PR/SZ bits when using extended mode */
108 #define _PAGE_CLEAR_FLAGS (_PAGE_PROTNONE | _PAGE_ACCESSED | \
109 _PAGE_PR_MASK | _PAGE_SZ_MASK)
110 #else
111 #define _PAGE_CLEAR_FLAGS (_PAGE_PROTNONE | _PAGE_ACCESSED)
112 #endif
113
114 #define _PAGE_FLAGS_HARDWARE_MASK (phys_addr_mask() & ~(_PAGE_CLEAR_FLAGS))
115
116 /* Hardware flags, page size encoding */
117 #if !defined(CONFIG_MMU)
118 # define _PAGE_FLAGS_HARD 0ULL
119 #elif defined(CONFIG_X2TLB)
120 # if defined(CONFIG_PAGE_SIZE_4KB)
121 # define _PAGE_FLAGS_HARD _PAGE_EXT(_PAGE_EXT_ESZ0)
122 # elif defined(CONFIG_PAGE_SIZE_8KB)
123 # define _PAGE_FLAGS_HARD _PAGE_EXT(_PAGE_EXT_ESZ1)
124 # elif defined(CONFIG_PAGE_SIZE_64KB)
125 # define _PAGE_FLAGS_HARD _PAGE_EXT(_PAGE_EXT_ESZ2)
126 # endif
127 #else
128 # if defined(CONFIG_PAGE_SIZE_4KB)
129 # define _PAGE_FLAGS_HARD _PAGE_SZ0
130 # elif defined(CONFIG_PAGE_SIZE_64KB)
131 # define _PAGE_FLAGS_HARD _PAGE_SZ1
132 # endif
133 #endif
134
135 #if defined(CONFIG_X2TLB)
136 # if defined(CONFIG_HUGETLB_PAGE_SIZE_64K)
137 # define _PAGE_SZHUGE (_PAGE_EXT_ESZ2)
138 # elif defined(CONFIG_HUGETLB_PAGE_SIZE_256K)
139 # define _PAGE_SZHUGE (_PAGE_EXT_ESZ0 | _PAGE_EXT_ESZ2)
140 # elif defined(CONFIG_HUGETLB_PAGE_SIZE_1MB)
141 # define _PAGE_SZHUGE (_PAGE_EXT_ESZ0 | _PAGE_EXT_ESZ1 | _PAGE_EXT_ESZ2)
142 # elif defined(CONFIG_HUGETLB_PAGE_SIZE_4MB)
143 # define _PAGE_SZHUGE (_PAGE_EXT_ESZ3)
144 # elif defined(CONFIG_HUGETLB_PAGE_SIZE_64MB)
145 # define _PAGE_SZHUGE (_PAGE_EXT_ESZ2 | _PAGE_EXT_ESZ3)
146 # endif
147 # define _PAGE_WIRED (_PAGE_EXT(_PAGE_EXT_WIRED))
148 #else
149 # if defined(CONFIG_HUGETLB_PAGE_SIZE_64K)
150 # define _PAGE_SZHUGE (_PAGE_SZ1)
151 # elif defined(CONFIG_HUGETLB_PAGE_SIZE_1MB)
152 # define _PAGE_SZHUGE (_PAGE_SZ0 | _PAGE_SZ1)
153 # endif
154 # define _PAGE_WIRED (0)
155 #endif
156
157 /*
158 * Stub out _PAGE_SZHUGE if we don't have a good definition for it,
159 * to make pte_mkhuge() happy.
160 */
161 #ifndef _PAGE_SZHUGE
162 # define _PAGE_SZHUGE (_PAGE_FLAGS_HARD)
163 #endif
164
165 /*
166 * Mask of bits that are to be preserved across pgprot changes.
167 */
168 #define _PAGE_CHG_MASK \
169 (PTE_MASK | _PAGE_ACCESSED | _PAGE_CACHABLE | \
170 _PAGE_DIRTY | _PAGE_SPECIAL)
171
172 #ifndef __ASSEMBLY__
173
174 #if defined(CONFIG_X2TLB) /* SH-X2 TLB */
175 #define PAGE_NONE __pgprot(_PAGE_PROTNONE | _PAGE_CACHABLE | \
176 _PAGE_ACCESSED | _PAGE_FLAGS_HARD)
177
178 #define PAGE_SHARED __pgprot(_PAGE_PRESENT | _PAGE_ACCESSED | \
179 _PAGE_CACHABLE | _PAGE_FLAGS_HARD | \
180 _PAGE_EXT(_PAGE_EXT_KERN_READ | \
181 _PAGE_EXT_KERN_WRITE | \
182 _PAGE_EXT_USER_READ | \
183 _PAGE_EXT_USER_WRITE))
184
185 #define PAGE_EXECREAD __pgprot(_PAGE_PRESENT | _PAGE_ACCESSED | \
186 _PAGE_CACHABLE | _PAGE_FLAGS_HARD | \
187 _PAGE_EXT(_PAGE_EXT_KERN_EXEC | \
188 _PAGE_EXT_KERN_READ | \
189 _PAGE_EXT_USER_EXEC | \
190 _PAGE_EXT_USER_READ))
191
192 #define PAGE_COPY PAGE_EXECREAD
193
194 #define PAGE_READONLY __pgprot(_PAGE_PRESENT | _PAGE_ACCESSED | \
195 _PAGE_CACHABLE | _PAGE_FLAGS_HARD | \
196 _PAGE_EXT(_PAGE_EXT_KERN_READ | \
197 _PAGE_EXT_USER_READ))
198
199 #define PAGE_WRITEONLY __pgprot(_PAGE_PRESENT | _PAGE_ACCESSED | \
200 _PAGE_CACHABLE | _PAGE_FLAGS_HARD | \
201 _PAGE_EXT(_PAGE_EXT_KERN_WRITE | \
202 _PAGE_EXT_USER_WRITE))
203
204 #define PAGE_RWX __pgprot(_PAGE_PRESENT | _PAGE_ACCESSED | \
205 _PAGE_CACHABLE | _PAGE_FLAGS_HARD | \
206 _PAGE_EXT(_PAGE_EXT_KERN_WRITE | \
207 _PAGE_EXT_KERN_READ | \
208 _PAGE_EXT_KERN_EXEC | \
209 _PAGE_EXT_USER_WRITE | \
210 _PAGE_EXT_USER_READ | \
211 _PAGE_EXT_USER_EXEC))
212
213 #define PAGE_KERNEL __pgprot(_PAGE_PRESENT | _PAGE_CACHABLE | \
214 _PAGE_DIRTY | _PAGE_ACCESSED | \
215 _PAGE_HW_SHARED | _PAGE_FLAGS_HARD | \
216 _PAGE_EXT(_PAGE_EXT_KERN_READ | \
217 _PAGE_EXT_KERN_WRITE | \
218 _PAGE_EXT_KERN_EXEC))
219
220 #define PAGE_KERNEL_NOCACHE \
221 __pgprot(_PAGE_PRESENT | _PAGE_DIRTY | \
222 _PAGE_ACCESSED | _PAGE_HW_SHARED | \
223 _PAGE_FLAGS_HARD | \
224 _PAGE_EXT(_PAGE_EXT_KERN_READ | \
225 _PAGE_EXT_KERN_WRITE | \
226 _PAGE_EXT_KERN_EXEC))
227
228 #define PAGE_KERNEL_RO __pgprot(_PAGE_PRESENT | _PAGE_CACHABLE | \
229 _PAGE_DIRTY | _PAGE_ACCESSED | \
230 _PAGE_HW_SHARED | _PAGE_FLAGS_HARD | \
231 _PAGE_EXT(_PAGE_EXT_KERN_READ | \
232 _PAGE_EXT_KERN_EXEC))
233
234 #define PAGE_KERNEL_PCC(slot, type) \
235 __pgprot(0)
236
237 #elif defined(CONFIG_MMU) /* SH-X TLB */
238 #define PAGE_NONE __pgprot(_PAGE_PROTNONE | _PAGE_CACHABLE | \
239 _PAGE_ACCESSED | _PAGE_FLAGS_HARD)
240
241 #define PAGE_SHARED __pgprot(_PAGE_PRESENT | _PAGE_RW | _PAGE_USER | \
242 _PAGE_CACHABLE | _PAGE_ACCESSED | \
243 _PAGE_FLAGS_HARD)
244
245 #define PAGE_COPY __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_CACHABLE | \
246 _PAGE_ACCESSED | _PAGE_FLAGS_HARD)
247
248 #define PAGE_READONLY __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_CACHABLE | \
249 _PAGE_ACCESSED | _PAGE_FLAGS_HARD)
250
251 #define PAGE_EXECREAD PAGE_READONLY
252 #define PAGE_RWX PAGE_SHARED
253 #define PAGE_WRITEONLY PAGE_SHARED
254
255 #define PAGE_KERNEL __pgprot(_PAGE_PRESENT | _PAGE_RW | _PAGE_CACHABLE | \
256 _PAGE_DIRTY | _PAGE_ACCESSED | \
257 _PAGE_HW_SHARED | _PAGE_FLAGS_HARD)
258
259 #define PAGE_KERNEL_NOCACHE \
260 __pgprot(_PAGE_PRESENT | _PAGE_RW | _PAGE_DIRTY | \
261 _PAGE_ACCESSED | _PAGE_HW_SHARED | \
262 _PAGE_FLAGS_HARD)
263
264 #define PAGE_KERNEL_RO __pgprot(_PAGE_PRESENT | _PAGE_CACHABLE | \
265 _PAGE_DIRTY | _PAGE_ACCESSED | \
266 _PAGE_HW_SHARED | _PAGE_FLAGS_HARD)
267
268 #define PAGE_KERNEL_PCC(slot, type) \
269 __pgprot(_PAGE_PRESENT | _PAGE_RW | _PAGE_DIRTY | \
270 _PAGE_ACCESSED | _PAGE_FLAGS_HARD | \
271 (slot ? _PAGE_PCC_AREA5 : _PAGE_PCC_AREA6) | \
272 (type))
273 #else /* no mmu */
274 #define PAGE_NONE __pgprot(0)
275 #define PAGE_SHARED __pgprot(0)
276 #define PAGE_COPY __pgprot(0)
277 #define PAGE_EXECREAD __pgprot(0)
278 #define PAGE_RWX __pgprot(0)
279 #define PAGE_READONLY __pgprot(0)
280 #define PAGE_WRITEONLY __pgprot(0)
281 #define PAGE_KERNEL __pgprot(0)
282 #define PAGE_KERNEL_NOCACHE __pgprot(0)
283 #define PAGE_KERNEL_RO __pgprot(0)
284
285 #define PAGE_KERNEL_PCC(slot, type) \
286 __pgprot(0)
287 #endif
288
289 #endif /* __ASSEMBLY__ */
290
291 #ifndef __ASSEMBLY__
292
293 /*
294 * Certain architectures need to do special things when PTEs
295 * within a page table are directly modified. Thus, the following
296 * hook is made available.
297 */
298 #ifdef CONFIG_X2TLB
299 static inline void set_pte(pte_t *ptep, pte_t pte)
300 {
301 ptep->pte_high = pte.pte_high;
302 smp_wmb();
303 ptep->pte_low = pte.pte_low;
304 }
305 #else
306 #define set_pte(pteptr, pteval) (*(pteptr) = pteval)
307 #endif
308
309 #define set_pte_at(mm,addr,ptep,pteval) set_pte(ptep,pteval)
310
311 /*
312 * (pmds are folded into pgds so this doesn't get actually called,
313 * but the define is needed for a generic inline function.)
314 */
315 #define set_pmd(pmdptr, pmdval) (*(pmdptr) = pmdval)
316
317 #define pfn_pte(pfn, prot) \
318 __pte(((unsigned long long)(pfn) << PAGE_SHIFT) | pgprot_val(prot))
319 #define pfn_pmd(pfn, prot) \
320 __pmd(((unsigned long long)(pfn) << PAGE_SHIFT) | pgprot_val(prot))
321
322 #define pte_none(x) (!pte_val(x))
323 #define pte_present(x) ((x).pte_low & (_PAGE_PRESENT | _PAGE_PROTNONE))
324
325 #define pte_clear(mm,addr,xp) do { set_pte_at(mm, addr, xp, __pte(0)); } while (0)
326
327 #define pmd_none(x) (!pmd_val(x))
328 #define pmd_present(x) (pmd_val(x))
329 #define pmd_clear(xp) do { set_pmd(xp, __pmd(0)); } while (0)
330 #define pmd_bad(x) (pmd_val(x) & ~PAGE_MASK)
331
332 #define pages_to_mb(x) ((x) >> (20-PAGE_SHIFT))
333 #define pte_page(x) pfn_to_page(pte_pfn(x))
334
335 /*
336 * The following only work if pte_present() is true.
337 * Undefined behaviour if not..
338 */
339 #define pte_not_present(pte) (!((pte).pte_low & _PAGE_PRESENT))
340 #define pte_dirty(pte) ((pte).pte_low & _PAGE_DIRTY)
341 #define pte_young(pte) ((pte).pte_low & _PAGE_ACCESSED)
342 #define pte_special(pte) ((pte).pte_low & _PAGE_SPECIAL)
343
344 #ifdef CONFIG_X2TLB
345 #define pte_write(pte) \
346 ((pte).pte_high & (_PAGE_EXT_USER_WRITE | _PAGE_EXT_KERN_WRITE))
347 #else
348 #define pte_write(pte) ((pte).pte_low & _PAGE_RW)
349 #endif
350
351 #define PTE_BIT_FUNC(h,fn,op) \
352 static inline pte_t pte_##fn(pte_t pte) { pte.pte_##h op; return pte; }
353
354 #ifdef CONFIG_X2TLB
355 /*
356 * We cheat a bit in the SH-X2 TLB case. As the permission bits are
357 * individually toggled (and user permissions are entirely decoupled from
358 * kernel permissions), we attempt to couple them a bit more sanely here.
359 */
360 PTE_BIT_FUNC(high, wrprotect, &= ~(_PAGE_EXT_USER_WRITE | _PAGE_EXT_KERN_WRITE));
361 PTE_BIT_FUNC(high, mkwrite, |= _PAGE_EXT_USER_WRITE | _PAGE_EXT_KERN_WRITE);
362 PTE_BIT_FUNC(high, mkhuge, |= _PAGE_SZHUGE);
363 #else
364 PTE_BIT_FUNC(low, wrprotect, &= ~_PAGE_RW);
365 PTE_BIT_FUNC(low, mkwrite, |= _PAGE_RW);
366 PTE_BIT_FUNC(low, mkhuge, |= _PAGE_SZHUGE);
367 #endif
368
369 PTE_BIT_FUNC(low, mkclean, &= ~_PAGE_DIRTY);
370 PTE_BIT_FUNC(low, mkdirty, |= _PAGE_DIRTY);
371 PTE_BIT_FUNC(low, mkold, &= ~_PAGE_ACCESSED);
372 PTE_BIT_FUNC(low, mkyoung, |= _PAGE_ACCESSED);
373 PTE_BIT_FUNC(low, mkspecial, |= _PAGE_SPECIAL);
374
375 /*
376 * Macro and implementation to make a page protection as uncachable.
377 */
378 #define pgprot_writecombine(prot) \
379 __pgprot(pgprot_val(prot) & ~_PAGE_CACHABLE)
380
381 #define pgprot_noncached pgprot_writecombine
382
383 /*
384 * Conversion functions: convert a page and protection to a page entry,
385 * and a page entry and page directory to the page they refer to.
386 *
387 * extern pte_t mk_pte(struct page *page, pgprot_t pgprot)
388 */
389 #define mk_pte(page, pgprot) pfn_pte(page_to_pfn(page), (pgprot))
390
391 static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
392 {
393 pte.pte_low &= _PAGE_CHG_MASK;
394 pte.pte_low |= pgprot_val(newprot);
395
396 #ifdef CONFIG_X2TLB
397 pte.pte_high |= pgprot_val(newprot) >> 32;
398 #endif
399
400 return pte;
401 }
402
403 #define pmd_page_vaddr(pmd) ((unsigned long)pmd_val(pmd))
404 #define pmd_page(pmd) (virt_to_page(pmd_val(pmd)))
405
406 /* to find an entry in a page-table-directory. */
407 #define pgd_index(address) (((address) >> PGDIR_SHIFT) & (PTRS_PER_PGD-1))
408 #define pgd_offset(mm, address) ((mm)->pgd + pgd_index(address))
409 #define __pgd_offset(address) pgd_index(address)
410
411 /* to find an entry in a kernel page-table-directory */
412 #define pgd_offset_k(address) pgd_offset(&init_mm, address)
413
414 #define __pud_offset(address) (((address) >> PUD_SHIFT) & (PTRS_PER_PUD-1))
415 #define __pmd_offset(address) (((address) >> PMD_SHIFT) & (PTRS_PER_PMD-1))
416
417 /* Find an entry in the third-level page table.. */
418 #define pte_index(address) ((address >> PAGE_SHIFT) & (PTRS_PER_PTE - 1))
419 #define __pte_offset(address) pte_index(address)
420
421 #define pte_offset_kernel(dir, address) \
422 ((pte_t *) pmd_page_vaddr(*(dir)) + pte_index(address))
423 #define pte_offset_map(dir, address) pte_offset_kernel(dir, address)
424 #define pte_unmap(pte) do { } while (0)
425
426 #ifdef CONFIG_X2TLB
427 #define pte_ERROR(e) \
428 printk("%s:%d: bad pte %p(%08lx%08lx).\n", __FILE__, __LINE__, \
429 &(e), (e).pte_high, (e).pte_low)
430 #define pgd_ERROR(e) \
431 printk("%s:%d: bad pgd %016llx.\n", __FILE__, __LINE__, pgd_val(e))
432 #else
433 #define pte_ERROR(e) \
434 printk("%s:%d: bad pte %08lx.\n", __FILE__, __LINE__, pte_val(e))
435 #define pgd_ERROR(e) \
436 printk("%s:%d: bad pgd %08lx.\n", __FILE__, __LINE__, pgd_val(e))
437 #endif
438
439 /*
440 * Encode and de-code a swap entry
441 *
442 * Constraints:
443 * _PAGE_PRESENT at bit 8
444 * _PAGE_PROTNONE at bit 9
445 *
446 * For the normal case, we encode the swap type into bits 0:7 and the
447 * swap offset into bits 10:30. For the 64-bit PTE case, we keep the
448 * preserved bits in the low 32-bits and use the upper 32 as the swap
449 * offset (along with a 5-bit type), following the same approach as x86
450 * PAE. This keeps the logic quite simple.
451 *
452 * As is evident by the Alpha code, if we ever get a 64-bit unsigned
453 * long (swp_entry_t) to match up with the 64-bit PTEs, this all becomes
454 * much cleaner..
455 *
456 * NOTE: We should set ZEROs at the position of _PAGE_PRESENT
457 * and _PAGE_PROTNONE bits
458 */
459 #ifdef CONFIG_X2TLB
460 #define __swp_type(x) ((x).val & 0x1f)
461 #define __swp_offset(x) ((x).val >> 5)
462 #define __swp_entry(type, offset) ((swp_entry_t){ (type) | (offset) << 5})
463 #define __pte_to_swp_entry(pte) ((swp_entry_t){ (pte).pte_high })
464 #define __swp_entry_to_pte(x) ((pte_t){ 0, (x).val })
465
466 #else
467 #define __swp_type(x) ((x).val & 0xff)
468 #define __swp_offset(x) ((x).val >> 10)
469 #define __swp_entry(type, offset) ((swp_entry_t){(type) | (offset) <<10})
470
471 #define __pte_to_swp_entry(pte) ((swp_entry_t) { pte_val(pte) >> 1 })
472 #define __swp_entry_to_pte(x) ((pte_t) { (x).val << 1 })
473 #endif
474
475 #endif /* __ASSEMBLY__ */
476 #endif /* __ASM_SH_PGTABLE_32_H */