pgtable-ppc64.h 16 KB

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  1. #ifndef _ASM_POWERPC_PGTABLE_PPC64_H_
  2. #define _ASM_POWERPC_PGTABLE_PPC64_H_
  3. /*
  4. * This file contains the functions and defines necessary to modify and use
  5. * the ppc64 hashed page table.
  6. */
  7. #ifndef __ASSEMBLY__
  8. #include <linux/stddef.h>
  9. #include <asm/processor.h> /* For TASK_SIZE */
  10. #include <asm/mmu.h>
  11. #include <asm/page.h>
  12. #include <asm/tlbflush.h>
  13. struct mm_struct;
  14. #endif /* __ASSEMBLY__ */
  15. #ifdef CONFIG_PPC_64K_PAGES
  16. #include <asm/pgtable-64k.h>
  17. #else
  18. #include <asm/pgtable-4k.h>
  19. #endif
  20. #define FIRST_USER_ADDRESS 0
  21. /*
  22. * Size of EA range mapped by our pagetables.
  23. */
  24. #define PGTABLE_EADDR_SIZE (PTE_INDEX_SIZE + PMD_INDEX_SIZE + \
  25. PUD_INDEX_SIZE + PGD_INDEX_SIZE + PAGE_SHIFT)
  26. #define PGTABLE_RANGE (1UL << PGTABLE_EADDR_SIZE)
  27. #if TASK_SIZE_USER64 > PGTABLE_RANGE
  28. #error TASK_SIZE_USER64 exceeds pagetable range
  29. #endif
  30. #if TASK_SIZE_USER64 > (1UL << (USER_ESID_BITS + SID_SHIFT))
  31. #error TASK_SIZE_USER64 exceeds user VSID range
  32. #endif
  33. /*
  34. * Define the address range of the vmalloc VM area.
  35. */
  36. #define VMALLOC_START ASM_CONST(0xD000000000000000)
  37. #define VMALLOC_SIZE ASM_CONST(0x80000000000)
  38. #define VMALLOC_END (VMALLOC_START + VMALLOC_SIZE)
  39. /*
  40. * Define the address range of the imalloc VM area.
  41. */
  42. #define PHBS_IO_BASE VMALLOC_END
  43. #define IMALLOC_BASE (PHBS_IO_BASE + 0x80000000ul) /* Reserve 2 gigs for PHBs */
  44. #define IMALLOC_END (VMALLOC_START + PGTABLE_RANGE)
  45. /*
  46. * Region IDs
  47. */
  48. #define REGION_SHIFT 60UL
  49. #define REGION_MASK (0xfUL << REGION_SHIFT)
  50. #define REGION_ID(ea) (((unsigned long)(ea)) >> REGION_SHIFT)
  51. #define VMALLOC_REGION_ID (REGION_ID(VMALLOC_START))
  52. #define KERNEL_REGION_ID (REGION_ID(PAGE_OFFSET))
  53. #define USER_REGION_ID (0UL)
  54. /*
  55. * Common bits in a linux-style PTE. These match the bits in the
  56. * (hardware-defined) PowerPC PTE as closely as possible. Additional
  57. * bits may be defined in pgtable-*.h
  58. */
  59. #define _PAGE_PRESENT 0x0001 /* software: pte contains a translation */
  60. #define _PAGE_USER 0x0002 /* matches one of the PP bits */
  61. #define _PAGE_FILE 0x0002 /* (!present only) software: pte holds file offset */
  62. #define _PAGE_EXEC 0x0004 /* No execute on POWER4 and newer (we invert) */
  63. #define _PAGE_GUARDED 0x0008
  64. #define _PAGE_COHERENT 0x0010 /* M: enforce memory coherence (SMP systems) */
  65. #define _PAGE_NO_CACHE 0x0020 /* I: cache inhibit */
  66. #define _PAGE_WRITETHRU 0x0040 /* W: cache write-through */
  67. #define _PAGE_DIRTY 0x0080 /* C: page changed */
  68. #define _PAGE_ACCESSED 0x0100 /* R: page referenced */
  69. #define _PAGE_RW 0x0200 /* software: user write access allowed */
  70. #define _PAGE_HASHPTE 0x0400 /* software: pte has an associated HPTE */
  71. #define _PAGE_BUSY 0x0800 /* software: PTE & hash are busy */
  72. #define _PAGE_BASE (_PAGE_PRESENT | _PAGE_ACCESSED | _PAGE_COHERENT)
  73. #define _PAGE_WRENABLE (_PAGE_RW | _PAGE_DIRTY)
  74. /* __pgprot defined in asm-powerpc/page.h */
  75. #define PAGE_NONE __pgprot(_PAGE_PRESENT | _PAGE_ACCESSED)
  76. #define PAGE_SHARED __pgprot(_PAGE_BASE | _PAGE_RW | _PAGE_USER)
  77. #define PAGE_SHARED_X __pgprot(_PAGE_BASE | _PAGE_RW | _PAGE_USER | _PAGE_EXEC)
  78. #define PAGE_COPY __pgprot(_PAGE_BASE | _PAGE_USER)
  79. #define PAGE_COPY_X __pgprot(_PAGE_BASE | _PAGE_USER | _PAGE_EXEC)
  80. #define PAGE_READONLY __pgprot(_PAGE_BASE | _PAGE_USER)
  81. #define PAGE_READONLY_X __pgprot(_PAGE_BASE | _PAGE_USER | _PAGE_EXEC)
  82. #define PAGE_KERNEL __pgprot(_PAGE_BASE | _PAGE_WRENABLE)
  83. #define PAGE_KERNEL_CI __pgprot(_PAGE_PRESENT | _PAGE_ACCESSED | \
  84. _PAGE_WRENABLE | _PAGE_NO_CACHE | _PAGE_GUARDED)
  85. #define PAGE_KERNEL_EXEC __pgprot(_PAGE_BASE | _PAGE_WRENABLE | _PAGE_EXEC)
  86. #define PAGE_AGP __pgprot(_PAGE_BASE | _PAGE_WRENABLE | _PAGE_NO_CACHE)
  87. #define HAVE_PAGE_AGP
  88. /* PTEIDX nibble */
  89. #define _PTEIDX_SECONDARY 0x8
  90. #define _PTEIDX_GROUP_IX 0x7
  91. /*
  92. * POWER4 and newer have per page execute protection, older chips can only
  93. * do this on a segment (256MB) basis.
  94. *
  95. * Also, write permissions imply read permissions.
  96. * This is the closest we can get..
  97. *
  98. * Note due to the way vm flags are laid out, the bits are XWR
  99. */
  100. #define __P000 PAGE_NONE
  101. #define __P001 PAGE_READONLY
  102. #define __P010 PAGE_COPY
  103. #define __P011 PAGE_COPY
  104. #define __P100 PAGE_READONLY_X
  105. #define __P101 PAGE_READONLY_X
  106. #define __P110 PAGE_COPY_X
  107. #define __P111 PAGE_COPY_X
  108. #define __S000 PAGE_NONE
  109. #define __S001 PAGE_READONLY
  110. #define __S010 PAGE_SHARED
  111. #define __S011 PAGE_SHARED
  112. #define __S100 PAGE_READONLY_X
  113. #define __S101 PAGE_READONLY_X
  114. #define __S110 PAGE_SHARED_X
  115. #define __S111 PAGE_SHARED_X
  116. #ifndef __ASSEMBLY__
  117. /*
  118. * ZERO_PAGE is a global shared page that is always zero: used
  119. * for zero-mapped memory areas etc..
  120. */
  121. extern unsigned long empty_zero_page[PAGE_SIZE/sizeof(unsigned long)];
  122. #define ZERO_PAGE(vaddr) (virt_to_page(empty_zero_page))
  123. #endif /* __ASSEMBLY__ */
  124. #ifdef CONFIG_HUGETLB_PAGE
  125. #define HAVE_ARCH_UNMAPPED_AREA
  126. #define HAVE_ARCH_UNMAPPED_AREA_TOPDOWN
  127. #endif
  128. #ifndef __ASSEMBLY__
  129. /*
  130. * Conversion functions: convert a page and protection to a page entry,
  131. * and a page entry and page directory to the page they refer to.
  132. *
  133. * mk_pte takes a (struct page *) as input
  134. */
  135. #define mk_pte(page, pgprot) pfn_pte(page_to_pfn(page), (pgprot))
  136. static inline pte_t pfn_pte(unsigned long pfn, pgprot_t pgprot)
  137. {
  138. pte_t pte;
  139. pte_val(pte) = (pfn << PTE_RPN_SHIFT) | pgprot_val(pgprot);
  140. return pte;
  141. }
  142. #define pte_modify(_pte, newprot) \
  143. (__pte((pte_val(_pte) & _PAGE_CHG_MASK) | pgprot_val(newprot)))
  144. #define pte_none(pte) ((pte_val(pte) & ~_PAGE_HPTEFLAGS) == 0)
  145. #define pte_present(pte) (pte_val(pte) & _PAGE_PRESENT)
  146. /* pte_clear moved to later in this file */
  147. #define pte_pfn(x) ((unsigned long)((pte_val(x)>>PTE_RPN_SHIFT)))
  148. #define pte_page(x) pfn_to_page(pte_pfn(x))
  149. #define PMD_BAD_BITS (PTE_TABLE_SIZE-1)
  150. #define PUD_BAD_BITS (PMD_TABLE_SIZE-1)
  151. #define pmd_set(pmdp, pmdval) (pmd_val(*(pmdp)) = (pmdval))
  152. #define pmd_none(pmd) (!pmd_val(pmd))
  153. #define pmd_bad(pmd) (!is_kernel_addr(pmd_val(pmd)) \
  154. || (pmd_val(pmd) & PMD_BAD_BITS))
  155. #define pmd_present(pmd) (pmd_val(pmd) != 0)
  156. #define pmd_clear(pmdp) (pmd_val(*(pmdp)) = 0)
  157. #define pmd_page_vaddr(pmd) (pmd_val(pmd) & ~PMD_MASKED_BITS)
  158. #define pmd_page(pmd) virt_to_page(pmd_page_vaddr(pmd))
  159. #define pud_set(pudp, pudval) (pud_val(*(pudp)) = (pudval))
  160. #define pud_none(pud) (!pud_val(pud))
  161. #define pud_bad(pud) (!is_kernel_addr(pud_val(pud)) \
  162. || (pud_val(pud) & PUD_BAD_BITS))
  163. #define pud_present(pud) (pud_val(pud) != 0)
  164. #define pud_clear(pudp) (pud_val(*(pudp)) = 0)
  165. #define pud_page_vaddr(pud) (pud_val(pud) & ~PUD_MASKED_BITS)
  166. #define pud_page(pud) virt_to_page(pud_page_vaddr(pud))
  167. #define pgd_set(pgdp, pudp) ({pgd_val(*(pgdp)) = (unsigned long)(pudp);})
  168. /*
  169. * Find an entry in a page-table-directory. We combine the address region
  170. * (the high order N bits) and the pgd portion of the address.
  171. */
  172. /* to avoid overflow in free_pgtables we don't use PTRS_PER_PGD here */
  173. #define pgd_index(address) (((address) >> (PGDIR_SHIFT)) & 0x1ff)
  174. #define pgd_offset(mm, address) ((mm)->pgd + pgd_index(address))
  175. #define pmd_offset(pudp,addr) \
  176. (((pmd_t *) pud_page_vaddr(*(pudp))) + (((addr) >> PMD_SHIFT) & (PTRS_PER_PMD - 1)))
  177. #define pte_offset_kernel(dir,addr) \
  178. (((pte_t *) pmd_page_vaddr(*(dir))) + (((addr) >> PAGE_SHIFT) & (PTRS_PER_PTE - 1)))
  179. #define pte_offset_map(dir,addr) pte_offset_kernel((dir), (addr))
  180. #define pte_offset_map_nested(dir,addr) pte_offset_kernel((dir), (addr))
  181. #define pte_unmap(pte) do { } while(0)
  182. #define pte_unmap_nested(pte) do { } while(0)
  183. /* to find an entry in a kernel page-table-directory */
  184. /* This now only contains the vmalloc pages */
  185. #define pgd_offset_k(address) pgd_offset(&init_mm, address)
  186. /*
  187. * The following only work if pte_present() is true.
  188. * Undefined behaviour if not..
  189. */
  190. static inline int pte_read(pte_t pte) { return pte_val(pte) & _PAGE_USER;}
  191. static inline int pte_write(pte_t pte) { return pte_val(pte) & _PAGE_RW;}
  192. static inline int pte_exec(pte_t pte) { return pte_val(pte) & _PAGE_EXEC;}
  193. static inline int pte_dirty(pte_t pte) { return pte_val(pte) & _PAGE_DIRTY;}
  194. static inline int pte_young(pte_t pte) { return pte_val(pte) & _PAGE_ACCESSED;}
  195. static inline int pte_file(pte_t pte) { return pte_val(pte) & _PAGE_FILE;}
  196. static inline void pte_uncache(pte_t pte) { pte_val(pte) |= _PAGE_NO_CACHE; }
  197. static inline void pte_cache(pte_t pte) { pte_val(pte) &= ~_PAGE_NO_CACHE; }
  198. static inline pte_t pte_rdprotect(pte_t pte) {
  199. pte_val(pte) &= ~_PAGE_USER; return pte; }
  200. static inline pte_t pte_exprotect(pte_t pte) {
  201. pte_val(pte) &= ~_PAGE_EXEC; return pte; }
  202. static inline pte_t pte_wrprotect(pte_t pte) {
  203. pte_val(pte) &= ~(_PAGE_RW); return pte; }
  204. static inline pte_t pte_mkclean(pte_t pte) {
  205. pte_val(pte) &= ~(_PAGE_DIRTY); return pte; }
  206. static inline pte_t pte_mkold(pte_t pte) {
  207. pte_val(pte) &= ~_PAGE_ACCESSED; return pte; }
  208. static inline pte_t pte_mkread(pte_t pte) {
  209. pte_val(pte) |= _PAGE_USER; return pte; }
  210. static inline pte_t pte_mkexec(pte_t pte) {
  211. pte_val(pte) |= _PAGE_USER | _PAGE_EXEC; return pte; }
  212. static inline pte_t pte_mkwrite(pte_t pte) {
  213. pte_val(pte) |= _PAGE_RW; return pte; }
  214. static inline pte_t pte_mkdirty(pte_t pte) {
  215. pte_val(pte) |= _PAGE_DIRTY; return pte; }
  216. static inline pte_t pte_mkyoung(pte_t pte) {
  217. pte_val(pte) |= _PAGE_ACCESSED; return pte; }
  218. static inline pte_t pte_mkhuge(pte_t pte) {
  219. return pte; }
  220. /* Atomic PTE updates */
  221. static inline unsigned long pte_update(struct mm_struct *mm,
  222. unsigned long addr,
  223. pte_t *ptep, unsigned long clr,
  224. int huge)
  225. {
  226. unsigned long old, tmp;
  227. __asm__ __volatile__(
  228. "1: ldarx %0,0,%3 # pte_update\n\
  229. andi. %1,%0,%6\n\
  230. bne- 1b \n\
  231. andc %1,%0,%4 \n\
  232. stdcx. %1,0,%3 \n\
  233. bne- 1b"
  234. : "=&r" (old), "=&r" (tmp), "=m" (*ptep)
  235. : "r" (ptep), "r" (clr), "m" (*ptep), "i" (_PAGE_BUSY)
  236. : "cc" );
  237. if (old & _PAGE_HASHPTE)
  238. hpte_need_flush(mm, addr, ptep, old, huge);
  239. return old;
  240. }
  241. static inline int __ptep_test_and_clear_young(struct mm_struct *mm,
  242. unsigned long addr, pte_t *ptep)
  243. {
  244. unsigned long old;
  245. if ((pte_val(*ptep) & (_PAGE_ACCESSED | _PAGE_HASHPTE)) == 0)
  246. return 0;
  247. old = pte_update(mm, addr, ptep, _PAGE_ACCESSED, 0);
  248. return (old & _PAGE_ACCESSED) != 0;
  249. }
  250. #define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG
  251. #define ptep_test_and_clear_young(__vma, __addr, __ptep) \
  252. ({ \
  253. int __r; \
  254. __r = __ptep_test_and_clear_young((__vma)->vm_mm, __addr, __ptep); \
  255. __r; \
  256. })
  257. /*
  258. * On RW/DIRTY bit transitions we can avoid flushing the hpte. For the
  259. * moment we always flush but we need to fix hpte_update and test if the
  260. * optimisation is worth it.
  261. */
  262. static inline int __ptep_test_and_clear_dirty(struct mm_struct *mm,
  263. unsigned long addr, pte_t *ptep)
  264. {
  265. unsigned long old;
  266. if ((pte_val(*ptep) & _PAGE_DIRTY) == 0)
  267. return 0;
  268. old = pte_update(mm, addr, ptep, _PAGE_DIRTY, 0);
  269. return (old & _PAGE_DIRTY) != 0;
  270. }
  271. #define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_DIRTY
  272. #define ptep_test_and_clear_dirty(__vma, __addr, __ptep) \
  273. ({ \
  274. int __r; \
  275. __r = __ptep_test_and_clear_dirty((__vma)->vm_mm, __addr, __ptep); \
  276. __r; \
  277. })
  278. #define __HAVE_ARCH_PTEP_SET_WRPROTECT
  279. static inline void ptep_set_wrprotect(struct mm_struct *mm, unsigned long addr,
  280. pte_t *ptep)
  281. {
  282. unsigned long old;
  283. if ((pte_val(*ptep) & _PAGE_RW) == 0)
  284. return;
  285. old = pte_update(mm, addr, ptep, _PAGE_RW, 0);
  286. }
  287. /*
  288. * We currently remove entries from the hashtable regardless of whether
  289. * the entry was young or dirty. The generic routines only flush if the
  290. * entry was young or dirty which is not good enough.
  291. *
  292. * We should be more intelligent about this but for the moment we override
  293. * these functions and force a tlb flush unconditionally
  294. */
  295. #define __HAVE_ARCH_PTEP_CLEAR_YOUNG_FLUSH
  296. #define ptep_clear_flush_young(__vma, __address, __ptep) \
  297. ({ \
  298. int __young = __ptep_test_and_clear_young((__vma)->vm_mm, __address, \
  299. __ptep); \
  300. __young; \
  301. })
  302. #define __HAVE_ARCH_PTEP_CLEAR_DIRTY_FLUSH
  303. #define ptep_clear_flush_dirty(__vma, __address, __ptep) \
  304. ({ \
  305. int __dirty = __ptep_test_and_clear_dirty((__vma)->vm_mm, __address, \
  306. __ptep); \
  307. __dirty; \
  308. })
  309. #define __HAVE_ARCH_PTEP_GET_AND_CLEAR
  310. static inline pte_t ptep_get_and_clear(struct mm_struct *mm,
  311. unsigned long addr, pte_t *ptep)
  312. {
  313. unsigned long old = pte_update(mm, addr, ptep, ~0UL, 0);
  314. return __pte(old);
  315. }
  316. static inline void pte_clear(struct mm_struct *mm, unsigned long addr,
  317. pte_t * ptep)
  318. {
  319. pte_update(mm, addr, ptep, ~0UL, 0);
  320. }
  321. /*
  322. * set_pte stores a linux PTE into the linux page table.
  323. */
  324. static inline void set_pte_at(struct mm_struct *mm, unsigned long addr,
  325. pte_t *ptep, pte_t pte)
  326. {
  327. if (pte_present(*ptep))
  328. pte_clear(mm, addr, ptep);
  329. pte = __pte(pte_val(pte) & ~_PAGE_HPTEFLAGS);
  330. *ptep = pte;
  331. }
  332. /* Set the dirty and/or accessed bits atomically in a linux PTE, this
  333. * function doesn't need to flush the hash entry
  334. */
  335. #define __HAVE_ARCH_PTEP_SET_ACCESS_FLAGS
  336. static inline void __ptep_set_access_flags(pte_t *ptep, pte_t entry, int dirty)
  337. {
  338. unsigned long bits = pte_val(entry) &
  339. (_PAGE_DIRTY | _PAGE_ACCESSED | _PAGE_RW | _PAGE_EXEC);
  340. unsigned long old, tmp;
  341. __asm__ __volatile__(
  342. "1: ldarx %0,0,%4\n\
  343. andi. %1,%0,%6\n\
  344. bne- 1b \n\
  345. or %0,%3,%0\n\
  346. stdcx. %0,0,%4\n\
  347. bne- 1b"
  348. :"=&r" (old), "=&r" (tmp), "=m" (*ptep)
  349. :"r" (bits), "r" (ptep), "m" (*ptep), "i" (_PAGE_BUSY)
  350. :"cc");
  351. }
  352. #define ptep_set_access_flags(__vma, __address, __ptep, __entry, __dirty) \
  353. do { \
  354. __ptep_set_access_flags(__ptep, __entry, __dirty); \
  355. flush_tlb_page_nohash(__vma, __address); \
  356. } while(0)
  357. /*
  358. * Macro to mark a page protection value as "uncacheable".
  359. */
  360. #define pgprot_noncached(prot) (__pgprot(pgprot_val(prot) | _PAGE_NO_CACHE | _PAGE_GUARDED))
  361. struct file;
  362. extern pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
  363. unsigned long size, pgprot_t vma_prot);
  364. #define __HAVE_PHYS_MEM_ACCESS_PROT
  365. #define __HAVE_ARCH_PTE_SAME
  366. #define pte_same(A,B) (((pte_val(A) ^ pte_val(B)) & ~_PAGE_HPTEFLAGS) == 0)
  367. #define pte_ERROR(e) \
  368. printk("%s:%d: bad pte %08lx.\n", __FILE__, __LINE__, pte_val(e))
  369. #define pmd_ERROR(e) \
  370. printk("%s:%d: bad pmd %08lx.\n", __FILE__, __LINE__, pmd_val(e))
  371. #define pgd_ERROR(e) \
  372. printk("%s:%d: bad pgd %08lx.\n", __FILE__, __LINE__, pgd_val(e))
  373. extern pgd_t swapper_pg_dir[];
  374. extern void paging_init(void);
  375. /* Encode and de-code a swap entry */
  376. #define __swp_type(entry) (((entry).val >> 1) & 0x3f)
  377. #define __swp_offset(entry) ((entry).val >> 8)
  378. #define __swp_entry(type, offset) ((swp_entry_t){((type)<< 1)|((offset)<<8)})
  379. #define __pte_to_swp_entry(pte) ((swp_entry_t){pte_val(pte) >> PTE_RPN_SHIFT})
  380. #define __swp_entry_to_pte(x) ((pte_t) { (x).val << PTE_RPN_SHIFT })
  381. #define pte_to_pgoff(pte) (pte_val(pte) >> PTE_RPN_SHIFT)
  382. #define pgoff_to_pte(off) ((pte_t) {((off) << PTE_RPN_SHIFT)|_PAGE_FILE})
  383. #define PTE_FILE_MAX_BITS (BITS_PER_LONG - PTE_RPN_SHIFT)
  384. /*
  385. * kern_addr_valid is intended to indicate whether an address is a valid
  386. * kernel address. Most 32-bit archs define it as always true (like this)
  387. * but most 64-bit archs actually perform a test. What should we do here?
  388. * The only use is in fs/ncpfs/dir.c
  389. */
  390. #define kern_addr_valid(addr) (1)
  391. #define io_remap_pfn_range(vma, vaddr, pfn, size, prot) \
  392. remap_pfn_range(vma, vaddr, pfn, size, prot)
  393. void pgtable_cache_init(void);
  394. /*
  395. * find_linux_pte returns the address of a linux pte for a given
  396. * effective address and directory. If not found, it returns zero.
  397. */static inline pte_t *find_linux_pte(pgd_t *pgdir, unsigned long ea)
  398. {
  399. pgd_t *pg;
  400. pud_t *pu;
  401. pmd_t *pm;
  402. pte_t *pt = NULL;
  403. pg = pgdir + pgd_index(ea);
  404. if (!pgd_none(*pg)) {
  405. pu = pud_offset(pg, ea);
  406. if (!pud_none(*pu)) {
  407. pm = pmd_offset(pu, ea);
  408. if (pmd_present(*pm))
  409. pt = pte_offset_kernel(pm, ea);
  410. }
  411. }
  412. return pt;
  413. }
  414. #endif /* __ASSEMBLY__ */
  415. #endif /* _ASM_POWERPC_PGTABLE_PPC64_H_ */