xref: /linux/arch/x86/mm/pgtable_32.c (revision 4f76cd382213b29dd3658e3e1ea47c0c2be06f3c)
1 #include <linux/sched.h>
2 #include <linux/kernel.h>
3 #include <linux/errno.h>
4 #include <linux/mm.h>
5 #include <linux/nmi.h>
6 #include <linux/swap.h>
7 #include <linux/smp.h>
8 #include <linux/highmem.h>
9 #include <linux/slab.h>
10 #include <linux/pagemap.h>
11 #include <linux/spinlock.h>
12 #include <linux/module.h>
13 #include <linux/quicklist.h>
14 
15 #include <asm/system.h>
16 #include <asm/pgtable.h>
17 #include <asm/pgalloc.h>
18 #include <asm/fixmap.h>
19 #include <asm/e820.h>
20 #include <asm/tlb.h>
21 #include <asm/tlbflush.h>
22 
23 void show_mem(void)
24 {
25 	int total = 0, reserved = 0;
26 	int shared = 0, cached = 0;
27 	int highmem = 0;
28 	struct page *page;
29 	pg_data_t *pgdat;
30 	unsigned long i;
31 	unsigned long flags;
32 
33 	printk(KERN_INFO "Mem-info:\n");
34 	show_free_areas();
35 	for_each_online_pgdat(pgdat) {
36 		pgdat_resize_lock(pgdat, &flags);
37 		for (i = 0; i < pgdat->node_spanned_pages; ++i) {
38 			if (unlikely(i % MAX_ORDER_NR_PAGES == 0))
39 				touch_nmi_watchdog();
40 			page = pgdat_page_nr(pgdat, i);
41 			total++;
42 			if (PageHighMem(page))
43 				highmem++;
44 			if (PageReserved(page))
45 				reserved++;
46 			else if (PageSwapCache(page))
47 				cached++;
48 			else if (page_count(page))
49 				shared += page_count(page) - 1;
50 		}
51 		pgdat_resize_unlock(pgdat, &flags);
52 	}
53 	printk(KERN_INFO "%d pages of RAM\n", total);
54 	printk(KERN_INFO "%d pages of HIGHMEM\n", highmem);
55 	printk(KERN_INFO "%d reserved pages\n", reserved);
56 	printk(KERN_INFO "%d pages shared\n", shared);
57 	printk(KERN_INFO "%d pages swap cached\n", cached);
58 
59 	printk(KERN_INFO "%lu pages dirty\n", global_page_state(NR_FILE_DIRTY));
60 	printk(KERN_INFO "%lu pages writeback\n",
61 					global_page_state(NR_WRITEBACK));
62 	printk(KERN_INFO "%lu pages mapped\n", global_page_state(NR_FILE_MAPPED));
63 	printk(KERN_INFO "%lu pages slab\n",
64 		global_page_state(NR_SLAB_RECLAIMABLE) +
65 		global_page_state(NR_SLAB_UNRECLAIMABLE));
66 	printk(KERN_INFO "%lu pages pagetables\n",
67 					global_page_state(NR_PAGETABLE));
68 }
69 
70 /*
71  * Associate a virtual page frame with a given physical page frame
72  * and protection flags for that frame.
73  */
74 static void set_pte_pfn(unsigned long vaddr, unsigned long pfn, pgprot_t flags)
75 {
76 	pgd_t *pgd;
77 	pud_t *pud;
78 	pmd_t *pmd;
79 	pte_t *pte;
80 
81 	pgd = swapper_pg_dir + pgd_index(vaddr);
82 	if (pgd_none(*pgd)) {
83 		BUG();
84 		return;
85 	}
86 	pud = pud_offset(pgd, vaddr);
87 	if (pud_none(*pud)) {
88 		BUG();
89 		return;
90 	}
91 	pmd = pmd_offset(pud, vaddr);
92 	if (pmd_none(*pmd)) {
93 		BUG();
94 		return;
95 	}
96 	pte = pte_offset_kernel(pmd, vaddr);
97 	if (pgprot_val(flags))
98 		set_pte_present(&init_mm, vaddr, pte, pfn_pte(pfn, flags));
99 	else
100 		pte_clear(&init_mm, vaddr, pte);
101 
102 	/*
103 	 * It's enough to flush this one mapping.
104 	 * (PGE mappings get flushed as well)
105 	 */
106 	__flush_tlb_one(vaddr);
107 }
108 
109 /*
110  * Associate a large virtual page frame with a given physical page frame
111  * and protection flags for that frame. pfn is for the base of the page,
112  * vaddr is what the page gets mapped to - both must be properly aligned.
113  * The pmd must already be instantiated. Assumes PAE mode.
114  */
115 void set_pmd_pfn(unsigned long vaddr, unsigned long pfn, pgprot_t flags)
116 {
117 	pgd_t *pgd;
118 	pud_t *pud;
119 	pmd_t *pmd;
120 
121 	if (vaddr & (PMD_SIZE-1)) {		/* vaddr is misaligned */
122 		printk(KERN_WARNING "set_pmd_pfn: vaddr misaligned\n");
123 		return; /* BUG(); */
124 	}
125 	if (pfn & (PTRS_PER_PTE-1)) {		/* pfn is misaligned */
126 		printk(KERN_WARNING "set_pmd_pfn: pfn misaligned\n");
127 		return; /* BUG(); */
128 	}
129 	pgd = swapper_pg_dir + pgd_index(vaddr);
130 	if (pgd_none(*pgd)) {
131 		printk(KERN_WARNING "set_pmd_pfn: pgd_none\n");
132 		return; /* BUG(); */
133 	}
134 	pud = pud_offset(pgd, vaddr);
135 	pmd = pmd_offset(pud, vaddr);
136 	set_pmd(pmd, pfn_pmd(pfn, flags));
137 	/*
138 	 * It's enough to flush this one mapping.
139 	 * (PGE mappings get flushed as well)
140 	 */
141 	__flush_tlb_one(vaddr);
142 }
143 
144 static int fixmaps;
145 unsigned long __FIXADDR_TOP = 0xfffff000;
146 EXPORT_SYMBOL(__FIXADDR_TOP);
147 
148 void __set_fixmap (enum fixed_addresses idx, unsigned long phys, pgprot_t flags)
149 {
150 	unsigned long address = __fix_to_virt(idx);
151 
152 	if (idx >= __end_of_fixed_addresses) {
153 		BUG();
154 		return;
155 	}
156 	set_pte_pfn(address, phys >> PAGE_SHIFT, flags);
157 	fixmaps++;
158 }
159 
160 /**
161  * reserve_top_address - reserves a hole in the top of kernel address space
162  * @reserve - size of hole to reserve
163  *
164  * Can be used to relocate the fixmap area and poke a hole in the top
165  * of kernel address space to make room for a hypervisor.
166  */
167 void reserve_top_address(unsigned long reserve)
168 {
169 	BUG_ON(fixmaps > 0);
170 	printk(KERN_INFO "Reserving virtual address space above 0x%08x\n",
171 	       (int)-reserve);
172 	__FIXADDR_TOP = -reserve - PAGE_SIZE;
173 	__VMALLOC_RESERVE += reserve;
174 }
175 
176 void __pte_free_tlb(struct mmu_gather *tlb, struct page *pte)
177 {
178 	pgtable_page_dtor(pte);
179 	paravirt_release_pt(page_to_pfn(pte));
180 	tlb_remove_page(tlb, pte);
181 }
182 
183 #ifdef CONFIG_X86_PAE
184 
185 void __pmd_free_tlb(struct mmu_gather *tlb, pmd_t *pmd)
186 {
187 	paravirt_release_pd(__pa(pmd) >> PAGE_SHIFT);
188 	tlb_remove_page(tlb, virt_to_page(pmd));
189 }
190 
191 #endif
192 
193 int pmd_bad(pmd_t pmd)
194 {
195 	WARN_ON_ONCE(pmd_bad_v1(pmd) != pmd_bad_v2(pmd));
196 
197 	return pmd_bad_v1(pmd);
198 }
199