Slab API: remove useless ctor parameter and reorder parameters
[linux-3.10.git] / arch / x86 / mm / pgtable_32.c
1 /*
2  *  linux/arch/i386/mm/pgtable.c
3  */
4
5 #include <linux/sched.h>
6 #include <linux/kernel.h>
7 #include <linux/errno.h>
8 #include <linux/mm.h>
9 #include <linux/swap.h>
10 #include <linux/smp.h>
11 #include <linux/highmem.h>
12 #include <linux/slab.h>
13 #include <linux/pagemap.h>
14 #include <linux/spinlock.h>
15 #include <linux/module.h>
16 #include <linux/quicklist.h>
17
18 #include <asm/system.h>
19 #include <asm/pgtable.h>
20 #include <asm/pgalloc.h>
21 #include <asm/fixmap.h>
22 #include <asm/e820.h>
23 #include <asm/tlb.h>
24 #include <asm/tlbflush.h>
25
26 void show_mem(void)
27 {
28         int total = 0, reserved = 0;
29         int shared = 0, cached = 0;
30         int highmem = 0;
31         struct page *page;
32         pg_data_t *pgdat;
33         unsigned long i;
34         unsigned long flags;
35
36         printk(KERN_INFO "Mem-info:\n");
37         show_free_areas();
38         printk(KERN_INFO "Free swap:       %6ldkB\n", nr_swap_pages<<(PAGE_SHIFT-10));
39         for_each_online_pgdat(pgdat) {
40                 pgdat_resize_lock(pgdat, &flags);
41                 for (i = 0; i < pgdat->node_spanned_pages; ++i) {
42                         page = pgdat_page_nr(pgdat, i);
43                         total++;
44                         if (PageHighMem(page))
45                                 highmem++;
46                         if (PageReserved(page))
47                                 reserved++;
48                         else if (PageSwapCache(page))
49                                 cached++;
50                         else if (page_count(page))
51                                 shared += page_count(page) - 1;
52                 }
53                 pgdat_resize_unlock(pgdat, &flags);
54         }
55         printk(KERN_INFO "%d pages of RAM\n", total);
56         printk(KERN_INFO "%d pages of HIGHMEM\n", highmem);
57         printk(KERN_INFO "%d reserved pages\n", reserved);
58         printk(KERN_INFO "%d pages shared\n", shared);
59         printk(KERN_INFO "%d pages swap cached\n", cached);
60
61         printk(KERN_INFO "%lu pages dirty\n", global_page_state(NR_FILE_DIRTY));
62         printk(KERN_INFO "%lu pages writeback\n",
63                                         global_page_state(NR_WRITEBACK));
64         printk(KERN_INFO "%lu pages mapped\n", global_page_state(NR_FILE_MAPPED));
65         printk(KERN_INFO "%lu pages slab\n",
66                 global_page_state(NR_SLAB_RECLAIMABLE) +
67                 global_page_state(NR_SLAB_UNRECLAIMABLE));
68         printk(KERN_INFO "%lu pages pagetables\n",
69                                         global_page_state(NR_PAGETABLE));
70 }
71
72 /*
73  * Associate a virtual page frame with a given physical page frame 
74  * and protection flags for that frame.
75  */ 
76 static void set_pte_pfn(unsigned long vaddr, unsigned long pfn, pgprot_t flags)
77 {
78         pgd_t *pgd;
79         pud_t *pud;
80         pmd_t *pmd;
81         pte_t *pte;
82
83         pgd = swapper_pg_dir + pgd_index(vaddr);
84         if (pgd_none(*pgd)) {
85                 BUG();
86                 return;
87         }
88         pud = pud_offset(pgd, vaddr);
89         if (pud_none(*pud)) {
90                 BUG();
91                 return;
92         }
93         pmd = pmd_offset(pud, vaddr);
94         if (pmd_none(*pmd)) {
95                 BUG();
96                 return;
97         }
98         pte = pte_offset_kernel(pmd, vaddr);
99         if (pgprot_val(flags))
100                 /* <pfn,flags> stored as-is, to permit clearing entries */
101                 set_pte(pte, pfn_pte(pfn, flags));
102         else
103                 pte_clear(&init_mm, vaddr, pte);
104
105         /*
106          * It's enough to flush this one mapping.
107          * (PGE mappings get flushed as well)
108          */
109         __flush_tlb_one(vaddr);
110 }
111
112 /*
113  * Associate a large virtual page frame with a given physical page frame 
114  * and protection flags for that frame. pfn is for the base of the page,
115  * vaddr is what the page gets mapped to - both must be properly aligned. 
116  * The pmd must already be instantiated. Assumes PAE mode.
117  */ 
118 void set_pmd_pfn(unsigned long vaddr, unsigned long pfn, pgprot_t flags)
119 {
120         pgd_t *pgd;
121         pud_t *pud;
122         pmd_t *pmd;
123
124         if (vaddr & (PMD_SIZE-1)) {             /* vaddr is misaligned */
125                 printk(KERN_WARNING "set_pmd_pfn: vaddr misaligned\n");
126                 return; /* BUG(); */
127         }
128         if (pfn & (PTRS_PER_PTE-1)) {           /* pfn is misaligned */
129                 printk(KERN_WARNING "set_pmd_pfn: pfn misaligned\n");
130                 return; /* BUG(); */
131         }
132         pgd = swapper_pg_dir + pgd_index(vaddr);
133         if (pgd_none(*pgd)) {
134                 printk(KERN_WARNING "set_pmd_pfn: pgd_none\n");
135                 return; /* BUG(); */
136         }
137         pud = pud_offset(pgd, vaddr);
138         pmd = pmd_offset(pud, vaddr);
139         set_pmd(pmd, pfn_pmd(pfn, flags));
140         /*
141          * It's enough to flush this one mapping.
142          * (PGE mappings get flushed as well)
143          */
144         __flush_tlb_one(vaddr);
145 }
146
147 static int fixmaps;
148 unsigned long __FIXADDR_TOP = 0xfffff000;
149 EXPORT_SYMBOL(__FIXADDR_TOP);
150
151 void __set_fixmap (enum fixed_addresses idx, unsigned long phys, pgprot_t flags)
152 {
153         unsigned long address = __fix_to_virt(idx);
154
155         if (idx >= __end_of_fixed_addresses) {
156                 BUG();
157                 return;
158         }
159         set_pte_pfn(address, phys >> PAGE_SHIFT, flags);
160         fixmaps++;
161 }
162
163 /**
164  * reserve_top_address - reserves a hole in the top of kernel address space
165  * @reserve - size of hole to reserve
166  *
167  * Can be used to relocate the fixmap area and poke a hole in the top
168  * of kernel address space to make room for a hypervisor.
169  */
170 void reserve_top_address(unsigned long reserve)
171 {
172         BUG_ON(fixmaps > 0);
173         printk(KERN_INFO "Reserving virtual address space above 0x%08x\n",
174                (int)-reserve);
175         __FIXADDR_TOP = -reserve - PAGE_SIZE;
176         __VMALLOC_RESERVE += reserve;
177 }
178
179 pte_t *pte_alloc_one_kernel(struct mm_struct *mm, unsigned long address)
180 {
181         return (pte_t *)__get_free_page(GFP_KERNEL|__GFP_REPEAT|__GFP_ZERO);
182 }
183
184 struct page *pte_alloc_one(struct mm_struct *mm, unsigned long address)
185 {
186         struct page *pte;
187
188 #ifdef CONFIG_HIGHPTE
189         pte = alloc_pages(GFP_KERNEL|__GFP_HIGHMEM|__GFP_REPEAT|__GFP_ZERO, 0);
190 #else
191         pte = alloc_pages(GFP_KERNEL|__GFP_REPEAT|__GFP_ZERO, 0);
192 #endif
193         return pte;
194 }
195
196 void pmd_ctor(struct kmem_cache *cache, void *pmd)
197 {
198         memset(pmd, 0, PTRS_PER_PMD*sizeof(pmd_t));
199 }
200
201 /*
202  * List of all pgd's needed for non-PAE so it can invalidate entries
203  * in both cached and uncached pgd's; not needed for PAE since the
204  * kernel pmd is shared. If PAE were not to share the pmd a similar
205  * tactic would be needed. This is essentially codepath-based locking
206  * against pageattr.c; it is the unique case in which a valid change
207  * of kernel pagetables can't be lazily synchronized by vmalloc faults.
208  * vmalloc faults work because attached pagetables are never freed.
209  * -- wli
210  */
211 DEFINE_SPINLOCK(pgd_lock);
212 struct page *pgd_list;
213
214 static inline void pgd_list_add(pgd_t *pgd)
215 {
216         struct page *page = virt_to_page(pgd);
217         page->index = (unsigned long)pgd_list;
218         if (pgd_list)
219                 set_page_private(pgd_list, (unsigned long)&page->index);
220         pgd_list = page;
221         set_page_private(page, (unsigned long)&pgd_list);
222 }
223
224 static inline void pgd_list_del(pgd_t *pgd)
225 {
226         struct page *next, **pprev, *page = virt_to_page(pgd);
227         next = (struct page *)page->index;
228         pprev = (struct page **)page_private(page);
229         *pprev = next;
230         if (next)
231                 set_page_private(next, (unsigned long)pprev);
232 }
233
234
235
236 #if (PTRS_PER_PMD == 1)
237 /* Non-PAE pgd constructor */
238 static void pgd_ctor(void *pgd)
239 {
240         unsigned long flags;
241
242         /* !PAE, no pagetable sharing */
243         memset(pgd, 0, USER_PTRS_PER_PGD*sizeof(pgd_t));
244
245         spin_lock_irqsave(&pgd_lock, flags);
246
247         /* must happen under lock */
248         clone_pgd_range((pgd_t *)pgd + USER_PTRS_PER_PGD,
249                         swapper_pg_dir + USER_PTRS_PER_PGD,
250                         KERNEL_PGD_PTRS);
251         paravirt_alloc_pd_clone(__pa(pgd) >> PAGE_SHIFT,
252                                 __pa(swapper_pg_dir) >> PAGE_SHIFT,
253                                 USER_PTRS_PER_PGD,
254                                 KERNEL_PGD_PTRS);
255         pgd_list_add(pgd);
256         spin_unlock_irqrestore(&pgd_lock, flags);
257 }
258 #else  /* PTRS_PER_PMD > 1 */
259 /* PAE pgd constructor */
260 static void pgd_ctor(void *pgd)
261 {
262         /* PAE, kernel PMD may be shared */
263
264         if (SHARED_KERNEL_PMD) {
265                 clone_pgd_range((pgd_t *)pgd + USER_PTRS_PER_PGD,
266                                 swapper_pg_dir + USER_PTRS_PER_PGD,
267                                 KERNEL_PGD_PTRS);
268         } else {
269                 unsigned long flags;
270
271                 memset(pgd, 0, USER_PTRS_PER_PGD*sizeof(pgd_t));
272                 spin_lock_irqsave(&pgd_lock, flags);
273                 pgd_list_add(pgd);
274                 spin_unlock_irqrestore(&pgd_lock, flags);
275         }
276 }
277 #endif  /* PTRS_PER_PMD */
278
279 static void pgd_dtor(void *pgd)
280 {
281         unsigned long flags; /* can be called from interrupt context */
282
283         if (SHARED_KERNEL_PMD)
284                 return;
285
286         paravirt_release_pd(__pa(pgd) >> PAGE_SHIFT);
287         spin_lock_irqsave(&pgd_lock, flags);
288         pgd_list_del(pgd);
289         spin_unlock_irqrestore(&pgd_lock, flags);
290 }
291
292 #define UNSHARED_PTRS_PER_PGD                           \
293         (SHARED_KERNEL_PMD ? USER_PTRS_PER_PGD : PTRS_PER_PGD)
294
295 /* If we allocate a pmd for part of the kernel address space, then
296    make sure its initialized with the appropriate kernel mappings.
297    Otherwise use a cached zeroed pmd.  */
298 static pmd_t *pmd_cache_alloc(int idx)
299 {
300         pmd_t *pmd;
301
302         if (idx >= USER_PTRS_PER_PGD) {
303                 pmd = (pmd_t *)__get_free_page(GFP_KERNEL);
304
305                 if (pmd)
306                         memcpy(pmd,
307                                (void *)pgd_page_vaddr(swapper_pg_dir[idx]),
308                                sizeof(pmd_t) * PTRS_PER_PMD);
309         } else
310                 pmd = kmem_cache_alloc(pmd_cache, GFP_KERNEL);
311
312         return pmd;
313 }
314
315 static void pmd_cache_free(pmd_t *pmd, int idx)
316 {
317         if (idx >= USER_PTRS_PER_PGD)
318                 free_page((unsigned long)pmd);
319         else
320                 kmem_cache_free(pmd_cache, pmd);
321 }
322
323 pgd_t *pgd_alloc(struct mm_struct *mm)
324 {
325         int i;
326         pgd_t *pgd = quicklist_alloc(0, GFP_KERNEL, pgd_ctor);
327
328         if (PTRS_PER_PMD == 1 || !pgd)
329                 return pgd;
330
331         for (i = 0; i < UNSHARED_PTRS_PER_PGD; ++i) {
332                 pmd_t *pmd = pmd_cache_alloc(i);
333
334                 if (!pmd)
335                         goto out_oom;
336
337                 paravirt_alloc_pd(__pa(pmd) >> PAGE_SHIFT);
338                 set_pgd(&pgd[i], __pgd(1 + __pa(pmd)));
339         }
340         return pgd;
341
342 out_oom:
343         for (i--; i >= 0; i--) {
344                 pgd_t pgdent = pgd[i];
345                 void* pmd = (void *)__va(pgd_val(pgdent)-1);
346                 paravirt_release_pd(__pa(pmd) >> PAGE_SHIFT);
347                 pmd_cache_free(pmd, i);
348         }
349         quicklist_free(0, pgd_dtor, pgd);
350         return NULL;
351 }
352
353 void pgd_free(pgd_t *pgd)
354 {
355         int i;
356
357         /* in the PAE case user pgd entries are overwritten before usage */
358         if (PTRS_PER_PMD > 1)
359                 for (i = 0; i < UNSHARED_PTRS_PER_PGD; ++i) {
360                         pgd_t pgdent = pgd[i];
361                         void* pmd = (void *)__va(pgd_val(pgdent)-1);
362                         paravirt_release_pd(__pa(pmd) >> PAGE_SHIFT);
363                         pmd_cache_free(pmd, i);
364                 }
365         /* in the non-PAE case, free_pgtables() clears user pgd entries */
366         quicklist_free(0, pgd_dtor, pgd);
367 }
368
369 void check_pgt_cache(void)
370 {
371         quicklist_trim(0, pgd_dtor, 25, 16);
372 }
373