File: /usr/src/linux/include/asm-ia64/pgalloc.h

1     #ifndef _ASM_IA64_PGALLOC_H
2     #define _ASM_IA64_PGALLOC_H
3     
4     /*
5      * This file contains the functions and defines necessary to allocate
6      * page tables.
7      *
8      * This hopefully works with any (fixed) ia-64 page-size, as defined
9      * in <asm/page.h> (currently 8192).
10      *
11      * Copyright (C) 1998-2001 Hewlett-Packard Co
12      * Copyright (C) 1998-2001 David Mosberger-Tang <davidm@hpl.hp.com>
13      * Copyright (C) 2000, Goutham Rao <goutham.rao@intel.com>
14      */
15     
16     #include <linux/config.h>
17     
18     #include <linux/mm.h>
19     #include <linux/threads.h>
20     
21     #include <asm/mmu_context.h>
22     #include <asm/processor.h>
23     
24     /*
25      * Very stupidly, we used to get new pgd's and pmd's, init their contents
26      * to point to the NULL versions of the next level page table, later on
27      * completely re-init them the same way, then free them up.  This wasted
28      * a lot of work and caused unnecessary memory traffic.  How broken...
29      * We fix this by caching them.
30      */
31     #define pgd_quicklist		(local_cpu_data->pgd_quick)
32     #define pmd_quicklist		(local_cpu_data->pmd_quick)
33     #define pte_quicklist		(local_cpu_data->pte_quick)
34     #define pgtable_cache_size	(local_cpu_data->pgtable_cache_sz)
35     
36     static inline pgd_t*
37     pgd_alloc_one_fast (struct mm_struct *mm)
38     {
39     	unsigned long *ret = pgd_quicklist;
40     
41     	if (__builtin_expect(ret != NULL, 1)) {
42     		pgd_quicklist = (unsigned long *)(*ret);
43     		ret[0] = 0;
44     		--pgtable_cache_size;
45     	} else
46     		ret = NULL;
47     	return (pgd_t *) ret;
48     }
49     
50     static inline pgd_t*
51     pgd_alloc (struct mm_struct *mm)
52     {
53     	/* the VM system never calls pgd_alloc_one_fast(), so we do it here. */
54     	pgd_t *pgd = pgd_alloc_one_fast(mm);
55     
56     	if (__builtin_expect(pgd == NULL, 0)) {
57     		pgd = (pgd_t *)__get_free_page(GFP_KERNEL);
58     		if (__builtin_expect(pgd != NULL, 1))
59     			clear_page(pgd);
60     	}
61     	return pgd;
62     }
63     
64     static inline void
65     pgd_free (pgd_t *pgd)
66     {
67     	*(unsigned long *)pgd = (unsigned long) pgd_quicklist;
68     	pgd_quicklist = (unsigned long *) pgd;
69     	++pgtable_cache_size;
70     }
71     
72     static inline void
73     pgd_populate (struct mm_struct *mm, pgd_t *pgd_entry, pmd_t *pmd)
74     {
75     	pgd_val(*pgd_entry) = __pa(pmd);
76     }
77     
78     
79     static inline pmd_t*
80     pmd_alloc_one_fast (struct mm_struct *mm, unsigned long addr)
81     {
82     	unsigned long *ret = (unsigned long *)pmd_quicklist;
83     
84     	if (__builtin_expect(ret != NULL, 1)) {
85     		pmd_quicklist = (unsigned long *)(*ret);
86     		ret[0] = 0;
87     		--pgtable_cache_size;
88     	}
89     	return (pmd_t *)ret;
90     }
91     
92     static inline pmd_t*
93     pmd_alloc_one (struct mm_struct *mm, unsigned long addr)
94     {
95     	pmd_t *pmd = (pmd_t *) __get_free_page(GFP_KERNEL);
96     
97     	if (__builtin_expect(pmd != NULL, 1))
98     		clear_page(pmd);
99     	return pmd;
100     }
101     
102     static inline void
103     pmd_free (pmd_t *pmd)
104     {
105     	*(unsigned long *)pmd = (unsigned long) pmd_quicklist;
106     	pmd_quicklist = (unsigned long *) pmd;
107     	++pgtable_cache_size;
108     }
109     
110     static inline void
111     pmd_populate (struct mm_struct *mm, pmd_t *pmd_entry, pte_t *pte)
112     {
113     	pmd_val(*pmd_entry) = __pa(pte);
114     }
115     
116     static inline pte_t*
117     pte_alloc_one_fast (struct mm_struct *mm, unsigned long addr)
118     {
119     	unsigned long *ret = (unsigned long *)pte_quicklist;
120     
121     	if (__builtin_expect(ret != NULL, 1)) {
122     		pte_quicklist = (unsigned long *)(*ret);
123     		ret[0] = 0;
124     		--pgtable_cache_size;
125     	}
126     	return (pte_t *)ret;
127     }
128     
129     
130     static inline pte_t*
131     pte_alloc_one (struct mm_struct *mm, unsigned long addr)
132     {
133     	pte_t *pte = (pte_t *) __get_free_page(GFP_KERNEL);
134     
135     	if (__builtin_expect(pte != NULL, 1))
136     		clear_page(pte);
137     	return pte;
138     }
139     
140     static inline void
141     pte_free (pte_t *pte)
142     {
143     	*(unsigned long *)pte = (unsigned long) pte_quicklist;
144     	pte_quicklist = (unsigned long *) pte;
145     	++pgtable_cache_size;
146     }
147     
148     extern int do_check_pgt_cache (int, int);
149     
150     /*
151      * Now for some TLB flushing routines.  This is the kind of stuff that
152      * can be very expensive, so try to avoid them whenever possible.
153      */
154     
155     /*
156      * Flush everything (kernel mapping may also have changed due to
157      * vmalloc/vfree).
158      */
159     extern void __flush_tlb_all (void);
160     
161     #ifdef CONFIG_SMP
162       extern void smp_flush_tlb_all (void);
163     # define flush_tlb_all()	smp_flush_tlb_all()
164     #else
165     # define flush_tlb_all()	__flush_tlb_all()
166     #endif
167     
168     /*
169      * Serialize usage of ptc.g:
170      */
171     extern spinlock_t ptcg_lock;
172     
173     /*
174      * Flush a specified user mapping
175      */
176     static inline void
177     flush_tlb_mm (struct mm_struct *mm)
178     {
179     	if (mm) {
180     		mm->context = 0;
181     		if (mm == current->active_mm) {
182     			/* This is called, e.g., as a result of exec().  */
183     			get_new_mmu_context(mm);
184     			reload_context(mm);
185     		}
186     	}
187     }
188     
189     extern void flush_tlb_range (struct mm_struct *mm, unsigned long start, unsigned long end);
190     
191     /*
192      * Page-granular tlb flush.
193      */
194     static inline void
195     flush_tlb_page (struct vm_area_struct *vma, unsigned long addr)
196     {
197     #ifdef CONFIG_SMP
198     	flush_tlb_range(vma->vm_mm, (addr & PAGE_MASK), (addr & PAGE_MASK) + PAGE_SIZE);
199     #else
200     	if (vma->vm_mm == current->active_mm)
201     		asm volatile ("ptc.l %0,%1" :: "r"(addr), "r"(PAGE_SHIFT << 2) : "memory");
202     #endif
203     }
204     
205     /*
206      * Flush the TLB entries mapping the virtually mapped linear page
207      * table corresponding to address range [START-END).
208      */
209     static inline void
210     flush_tlb_pgtables (struct mm_struct *mm, unsigned long start, unsigned long end)
211     {
212     	if (rgn_index(start) != rgn_index(end))
213     		printk("flush_tlb_pgtables: can't flush across regions!!\n");
214     	flush_tlb_range(mm, ia64_thash(start), ia64_thash(end));
215     }
216     
217     /*
218      * Now for some cache flushing routines.  This is the kind of stuff
219      * that can be very expensive, so try to avoid them whenever possible.
220      */
221     
222     /* Caches aren't brain-dead on the IA-64. */
223     #define flush_cache_all()			do { } while (0)
224     #define flush_cache_mm(mm)			do { } while (0)
225     #define flush_cache_range(mm, start, end)	do { } while (0)
226     #define flush_cache_page(vma, vmaddr)		do { } while (0)
227     #define flush_page_to_ram(page)			do { } while (0)
228     
229     extern void flush_icache_range (unsigned long start, unsigned long end);
230     
231     static inline void
232     flush_dcache_page (struct page *page)
233     {
234     	clear_bit(PG_arch_1, &page->flags);
235     }
236     
237     static inline void
238     clear_user_page (void *addr, unsigned long vaddr, struct page *page)
239     {
240     	clear_page(addr);
241     	flush_dcache_page(page);
242     }
243     
244     static inline void
245     copy_user_page (void *to, void *from, unsigned long vaddr, struct page *page)
246     {
247     	copy_page(to, from);
248     	flush_dcache_page(page);
249     }
250     
251     /*
252      * IA-64 doesn't have any external MMU info: the page tables contain all the necessary
253      * information.  However, we use this macro to take care of any (delayed) i-cache flushing
254      * that may be necessary.
255      */
256     static inline void
257     update_mmu_cache (struct vm_area_struct *vma, unsigned long vaddr, pte_t pte)
258     {
259     	unsigned long addr;
260     	struct page *page;
261     
262     	if (!pte_exec(pte))
263     		return;				/* not an executable page... */
264     
265     	page = pte_page(pte);
266     	/* don't use VADDR: it may not be mapped on this CPU (or may have just been flushed): */
267     	addr = (unsigned long) page_address(page);
268     
269     	if (test_bit(PG_arch_1, &page->flags))
270     		return;				/* i-cache is already coherent with d-cache */
271     
272     	flush_icache_range(addr, addr + PAGE_SIZE);
273     	set_bit(PG_arch_1, &page->flags);	/* mark page as clean */
274     }
275     
276     #endif /* _ASM_IA64_PGALLOC_H */
277