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/pagemap.h>
10 #include <linux/spinlock.h>
11 #include <linux/module.h>
12
13 #include <asm/pgtable.h>
14 #include <asm/pgalloc.h>
15 #include <asm/fixmap.h>
16 #include <asm/e820.h>
17 #include <asm/tlb.h>
18 #include <asm/tlbflush.h>
19 #include <asm/io.h>
20
21 unsigned int __VMALLOC_RESERVE = 128 << 20;
22
23 /*
24 * Associate a virtual page frame with a given physical page frame
25 * and protection flags for that frame.
26 */
set_pte_vaddr(unsigned long vaddr,pte_t pteval)27 void set_pte_vaddr(unsigned long vaddr, pte_t pteval)
28 {
29 pgd_t *pgd;
30 pud_t *pud;
31 pmd_t *pmd;
32 pte_t *pte;
33
34 pgd = swapper_pg_dir + pgd_index(vaddr);
35 if (pgd_none(*pgd)) {
36 BUG();
37 return;
38 }
39 pud = pud_offset(pgd, vaddr);
40 if (pud_none(*pud)) {
41 BUG();
42 return;
43 }
44 pmd = pmd_offset(pud, vaddr);
45 if (pmd_none(*pmd)) {
46 BUG();
47 return;
48 }
49 pte = pte_offset_kernel(pmd, vaddr);
50 if (pte_val(pteval))
51 set_pte_at(&init_mm, vaddr, pte, pteval);
52 else
53 pte_clear(&init_mm, vaddr, pte);
54
55 /*
56 * It's enough to flush this one mapping.
57 * (PGE mappings get flushed as well)
58 */
59 __flush_tlb_one(vaddr);
60 }
61
62 /*
63 * Associate a large virtual page frame with a given physical page frame
64 * and protection flags for that frame. pfn is for the base of the page,
65 * vaddr is what the page gets mapped to - both must be properly aligned.
66 * The pmd must already be instantiated. Assumes PAE mode.
67 */
set_pmd_pfn(unsigned long vaddr,unsigned long pfn,pgprot_t flags)68 void set_pmd_pfn(unsigned long vaddr, unsigned long pfn, pgprot_t flags)
69 {
70 pgd_t *pgd;
71 pud_t *pud;
72 pmd_t *pmd;
73
74 if (vaddr & (PMD_SIZE-1)) { /* vaddr is misaligned */
75 printk(KERN_WARNING "set_pmd_pfn: vaddr misaligned\n");
76 return; /* BUG(); */
77 }
78 if (pfn & (PTRS_PER_PTE-1)) { /* pfn is misaligned */
79 printk(KERN_WARNING "set_pmd_pfn: pfn misaligned\n");
80 return; /* BUG(); */
81 }
82 pgd = swapper_pg_dir + pgd_index(vaddr);
83 if (pgd_none(*pgd)) {
84 printk(KERN_WARNING "set_pmd_pfn: pgd_none\n");
85 return; /* BUG(); */
86 }
87 pud = pud_offset(pgd, vaddr);
88 pmd = pmd_offset(pud, vaddr);
89 set_pmd(pmd, pfn_pmd(pfn, flags));
90 /*
91 * It's enough to flush this one mapping.
92 * (PGE mappings get flushed as well)
93 */
94 __flush_tlb_one(vaddr);
95 }
96
97 unsigned long __FIXADDR_TOP = 0xfffff000;
98 EXPORT_SYMBOL(__FIXADDR_TOP);
99
100 /*
101 * vmalloc=size forces the vmalloc area to be exactly 'size'
102 * bytes. This can be used to increase (or decrease) the
103 * vmalloc area - the default is 128m.
104 */
parse_vmalloc(char * arg)105 static int __init parse_vmalloc(char *arg)
106 {
107 if (!arg)
108 return -EINVAL;
109
110 /* Add VMALLOC_OFFSET to the parsed value due to vm area guard hole*/
111 __VMALLOC_RESERVE = memparse(arg, &arg) + VMALLOC_OFFSET;
112 return 0;
113 }
114 early_param("vmalloc", parse_vmalloc);
115
116 /*
117 * reservetop=size reserves a hole at the top of the kernel address space which
118 * a hypervisor can load into later. Needed for dynamically loaded hypervisors,
119 * so relocating the fixmap can be done before paging initialization.
120 */
parse_reservetop(char * arg)121 static int __init parse_reservetop(char *arg)
122 {
123 unsigned long address;
124
125 if (!arg)
126 return -EINVAL;
127
128 address = memparse(arg, &arg);
129 reserve_top_address(address);
130 fixup_early_ioremap();
131 return 0;
132 }
133 early_param("reservetop", parse_reservetop);
134