1 #ifndef _ASM_IA64_TLB_H
2 #define _ASM_IA64_TLB_H
4 * Based on <asm-generic/tlb.h>.
6 * Copyright (C) 2002-2003 Hewlett-Packard Co
7 * David Mosberger-Tang <davidm@hpl.hp.com>
10 * Removing a translation from a page table (including TLB-shootdown) is a four-step
13 * (1) Flush (virtual) caches --- ensures virtual memory is coherent with kernel memory
14 * (this is a no-op on ia64).
15 * (2) Clear the relevant portions of the page-table
16 * (3) Flush the TLBs --- ensures that stale content is gone from CPU TLBs
17 * (4) Release the pages that were freed up in step (2).
19 * Note that the ordering of these steps is crucial to avoid races on MP machines.
21 * The Linux kernel defines several platform-specific hooks for TLB-shootdown. When
22 * unmapping a portion of the virtual address space, these hooks are called according to
23 * the following template:
25 * tlb <- tlb_gather_mmu(mm, start, end); // start unmap for address space MM
27 * for each vma that needs a shootdown do {
28 * tlb_start_vma(tlb, vma);
29 * for each page-table-entry PTE that needs to be removed do {
30 * tlb_remove_tlb_entry(tlb, pte, address);
31 * if (pte refers to a normal page) {
32 * tlb_remove_page(tlb, page);
35 * tlb_end_vma(tlb, vma);
38 * tlb_finish_mmu(tlb, start, end); // finish unmap for address space MM
41 #include <linux/pagemap.h>
42 #include <linux/swap.h>
44 #include <asm/pgalloc.h>
45 #include <asm/processor.h>
46 #include <asm/tlbflush.h>
47 #include <asm/machvec.h>
50 * If we can't allocate a page to make a big batch of page pointers
51 * to work on, then just handle a few from the on-stack structure.
53 #define IA64_GATHER_BUNDLE 8
59 unsigned char fullmm
; /* non-zero means full mm flush */
60 unsigned char need_flush
; /* really unmapped some PTEs? */
61 unsigned long start
, end
;
62 unsigned long start_addr
;
63 unsigned long end_addr
;
65 struct page
*local
[IA64_GATHER_BUNDLE
];
68 struct ia64_tr_entry
{
73 }; /*Record for tr entry!*/
75 extern int ia64_itr_entry(u64 target_mask
, u64 va
, u64 pte
, u64 log_size
);
76 extern void ia64_ptr_entry(u64 target_mask
, int slot
);
78 extern struct ia64_tr_entry
*ia64_idtrs
[NR_CPUS
];
81 region register macros
83 #define RR_TO_VE(val) (((val) >> 0) & 0x0000000000000001)
84 #define RR_VE(val) (((val) & 0x0000000000000001) << 0)
85 #define RR_VE_MASK 0x0000000000000001L
87 #define RR_TO_PS(val) (((val) >> 2) & 0x000000000000003f)
88 #define RR_PS(val) (((val) & 0x000000000000003f) << 2)
89 #define RR_PS_MASK 0x00000000000000fcL
91 #define RR_RID_MASK 0x00000000ffffff00L
92 #define RR_TO_RID(val) ((val >> 8) & 0xffffff)
95 * Flush the TLB for address range START to END and, if not in fast mode, release the
96 * freed pages that where gathered up to this point.
99 ia64_tlb_flush_mmu (struct mmu_gather
*tlb
, unsigned long start
, unsigned long end
)
104 if (!tlb
->need_flush
)
110 * Tearing down the entire address space. This happens both as a result
111 * of exit() and execve(). The latter case necessitates the call to
112 * flush_tlb_mm() here.
114 flush_tlb_mm(tlb
->mm
);
115 } else if (unlikely (end
- start
>= 1024*1024*1024*1024UL
116 || REGION_NUMBER(start
) != REGION_NUMBER(end
- 1)))
119 * If we flush more than a tera-byte or across regions, we're probably
120 * better off just flushing the entire TLB(s). This should be very rare
121 * and is not worth optimizing for.
126 * XXX fix me: flush_tlb_range() should take an mm pointer instead of a
129 struct vm_area_struct vma
;
132 /* flush the address range from the tlb: */
133 flush_tlb_range(&vma
, start
, end
);
134 /* now flush the virt. page-table area mapping the address range: */
135 flush_tlb_range(&vma
, ia64_thash(start
), ia64_thash(end
));
138 /* lastly, release the freed pages */
142 tlb
->start_addr
= ~0UL;
143 for (i
= 0; i
< nr
; ++i
)
144 free_page_and_swap_cache(tlb
->pages
[i
]);
147 static inline void __tlb_alloc_page(struct mmu_gather
*tlb
)
149 unsigned long addr
= __get_free_pages(GFP_NOWAIT
| __GFP_NOWARN
, 0);
152 tlb
->pages
= (void *)addr
;
153 tlb
->max
= PAGE_SIZE
/ sizeof(void *);
159 tlb_gather_mmu(struct mmu_gather
*tlb
, struct mm_struct
*mm
, unsigned long start
, unsigned long end
)
162 tlb
->max
= ARRAY_SIZE(tlb
->local
);
163 tlb
->pages
= tlb
->local
;
165 tlb
->fullmm
= !(start
| (end
+1));
168 tlb
->start_addr
= ~0UL;
172 * Called at the end of the shootdown operation to free up any resources that were
176 tlb_finish_mmu(struct mmu_gather
*tlb
, unsigned long start
, unsigned long end
)
179 * Note: tlb->nr may be 0 at this point, so we can't rely on tlb->start_addr and
182 ia64_tlb_flush_mmu(tlb
, start
, end
);
184 /* keep the page table cache within bounds */
187 if (tlb
->pages
!= tlb
->local
)
188 free_pages((unsigned long)tlb
->pages
, 0);
192 * Logically, this routine frees PAGE. On MP machines, the actual freeing of the page
193 * must be delayed until after the TLB has been flushed (see comments at the beginning of
196 static inline int __tlb_remove_page(struct mmu_gather
*tlb
, struct page
*page
)
200 if (!tlb
->nr
&& tlb
->pages
== tlb
->local
)
201 __tlb_alloc_page(tlb
);
203 tlb
->pages
[tlb
->nr
++] = page
;
204 VM_BUG_ON(tlb
->nr
> tlb
->max
);
206 return tlb
->max
- tlb
->nr
;
209 static inline void tlb_flush_mmu(struct mmu_gather
*tlb
)
211 ia64_tlb_flush_mmu(tlb
, tlb
->start_addr
, tlb
->end_addr
);
214 static inline void tlb_remove_page(struct mmu_gather
*tlb
, struct page
*page
)
216 if (!__tlb_remove_page(tlb
, page
))
221 * Remove TLB entry for PTE mapped at virtual address ADDRESS. This is called for any
222 * PTE, not just those pointing to (normal) physical memory.
225 __tlb_remove_tlb_entry (struct mmu_gather
*tlb
, pte_t
*ptep
, unsigned long address
)
227 if (tlb
->start_addr
== ~0UL)
228 tlb
->start_addr
= address
;
229 tlb
->end_addr
= address
+ PAGE_SIZE
;
232 #define tlb_migrate_finish(mm) platform_tlb_migrate_finish(mm)
234 #define tlb_start_vma(tlb, vma) do { } while (0)
235 #define tlb_end_vma(tlb, vma) do { } while (0)
237 #define tlb_remove_tlb_entry(tlb, ptep, addr) \
239 tlb->need_flush = 1; \
240 __tlb_remove_tlb_entry(tlb, ptep, addr); \
243 #define pte_free_tlb(tlb, ptep, address) \
245 tlb->need_flush = 1; \
246 __pte_free_tlb(tlb, ptep, address); \
249 #define pmd_free_tlb(tlb, ptep, address) \
251 tlb->need_flush = 1; \
252 __pmd_free_tlb(tlb, ptep, address); \
255 #define pud_free_tlb(tlb, pudp, address) \
257 tlb->need_flush = 1; \
258 __pud_free_tlb(tlb, pudp, address); \
261 #endif /* _ASM_IA64_TLB_H */