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 */ 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 unsigned long __FIXADDR_TOP = 0xfffff000; 63 EXPORT_SYMBOL(__FIXADDR_TOP); 64 65 /* 66 * vmalloc=size forces the vmalloc area to be exactly 'size' 67 * bytes. This can be used to increase (or decrease) the 68 * vmalloc area - the default is 128m. 69 */ 70 static int __init parse_vmalloc(char *arg) 71 { 72 if (!arg) 73 return -EINVAL; 74 75 /* Add VMALLOC_OFFSET to the parsed value due to vm area guard hole*/ 76 __VMALLOC_RESERVE = memparse(arg, &arg) + VMALLOC_OFFSET; 77 return 0; 78 } 79 early_param("vmalloc", parse_vmalloc); 80 81 /* 82 * reservetop=size reserves a hole at the top of the kernel address space which 83 * a hypervisor can load into later. Needed for dynamically loaded hypervisors, 84 * so relocating the fixmap can be done before paging initialization. 85 */ 86 static int __init parse_reservetop(char *arg) 87 { 88 unsigned long address; 89 90 if (!arg) 91 return -EINVAL; 92 93 address = memparse(arg, &arg); 94 reserve_top_address(address); 95 early_ioremap_init(); 96 return 0; 97 } 98 early_param("reservetop", parse_reservetop); 99