| Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 1 | // SPDX-License-Identifier: GPL-2.0 |
| 2 | #include <linux/sched.h> |
| 3 | #include <linux/kernel.h> |
| 4 | #include <linux/errno.h> |
| 5 | #include <linux/mm.h> |
| 6 | #include <linux/nmi.h> |
| 7 | #include <linux/swap.h> |
| 8 | #include <linux/smp.h> |
| 9 | #include <linux/highmem.h> |
| 10 | #include <linux/pagemap.h> |
| 11 | #include <linux/spinlock.h> |
| 12 | |
| 13 | #include <asm/cpu_entry_area.h> |
| 14 | #include <asm/pgtable.h> |
| 15 | #include <asm/pgalloc.h> |
| 16 | #include <asm/fixmap.h> |
| 17 | #include <asm/e820/api.h> |
| 18 | #include <asm/tlb.h> |
| 19 | #include <asm/tlbflush.h> |
| 20 | #include <asm/io.h> |
| 21 | |
| 22 | unsigned int __VMALLOC_RESERVE = 128 << 20; |
| 23 | |
| 24 | /* |
| 25 | * Associate a virtual page frame with a given physical page frame |
| 26 | * and protection flags for that frame. |
| 27 | */ |
| 28 | void set_pte_vaddr(unsigned long vaddr, pte_t pteval) |
| 29 | { |
| 30 | pgd_t *pgd; |
| 31 | p4d_t *p4d; |
| 32 | pud_t *pud; |
| 33 | pmd_t *pmd; |
| 34 | pte_t *pte; |
| 35 | |
| 36 | pgd = swapper_pg_dir + pgd_index(vaddr); |
| 37 | if (pgd_none(*pgd)) { |
| 38 | BUG(); |
| 39 | return; |
| 40 | } |
| 41 | p4d = p4d_offset(pgd, vaddr); |
| 42 | if (p4d_none(*p4d)) { |
| 43 | BUG(); |
| 44 | return; |
| 45 | } |
| 46 | pud = pud_offset(p4d, vaddr); |
| 47 | if (pud_none(*pud)) { |
| 48 | BUG(); |
| 49 | return; |
| 50 | } |
| 51 | pmd = pmd_offset(pud, vaddr); |
| 52 | if (pmd_none(*pmd)) { |
| 53 | BUG(); |
| 54 | return; |
| 55 | } |
| 56 | pte = pte_offset_kernel(pmd, vaddr); |
| 57 | if (!pte_none(pteval)) |
| 58 | set_pte_at(&init_mm, vaddr, pte, pteval); |
| 59 | else |
| 60 | pte_clear(&init_mm, vaddr, pte); |
| 61 | |
| 62 | /* |
| 63 | * It's enough to flush this one mapping. |
| 64 | * (PGE mappings get flushed as well) |
| 65 | */ |
| 66 | __flush_tlb_one_kernel(vaddr); |
| 67 | } |
| 68 | |
| 69 | unsigned long __FIXADDR_TOP = 0xfffff000; |
| 70 | EXPORT_SYMBOL(__FIXADDR_TOP); |
| 71 | |
| 72 | /* |
| 73 | * vmalloc=size forces the vmalloc area to be exactly 'size' |
| 74 | * bytes. This can be used to increase (or decrease) the |
| 75 | * vmalloc area - the default is 128m. |
| 76 | */ |
| 77 | static int __init parse_vmalloc(char *arg) |
| 78 | { |
| 79 | if (!arg) |
| 80 | return -EINVAL; |
| 81 | |
| 82 | /* Add VMALLOC_OFFSET to the parsed value due to vm area guard hole*/ |
| 83 | __VMALLOC_RESERVE = memparse(arg, &arg) + VMALLOC_OFFSET; |
| 84 | return 0; |
| 85 | } |
| 86 | early_param("vmalloc", parse_vmalloc); |
| 87 | |
| 88 | /* |
| 89 | * reservetop=size reserves a hole at the top of the kernel address space which |
| 90 | * a hypervisor can load into later. Needed for dynamically loaded hypervisors, |
| 91 | * so relocating the fixmap can be done before paging initialization. |
| 92 | */ |
| 93 | static int __init parse_reservetop(char *arg) |
| 94 | { |
| 95 | unsigned long address; |
| 96 | |
| 97 | if (!arg) |
| 98 | return -EINVAL; |
| 99 | |
| 100 | address = memparse(arg, &arg); |
| 101 | reserve_top_address(address); |
| 102 | early_ioremap_init(); |
| 103 | return 0; |
| 104 | } |
| 105 | early_param("reservetop", parse_reservetop); |