1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0
2*4882a593Smuzhiyun #include <linux/sched.h>
3*4882a593Smuzhiyun #include <linux/kernel.h>
4*4882a593Smuzhiyun #include <linux/errno.h>
5*4882a593Smuzhiyun #include <linux/mm.h>
6*4882a593Smuzhiyun #include <linux/nmi.h>
7*4882a593Smuzhiyun #include <linux/swap.h>
8*4882a593Smuzhiyun #include <linux/smp.h>
9*4882a593Smuzhiyun #include <linux/highmem.h>
10*4882a593Smuzhiyun #include <linux/pagemap.h>
11*4882a593Smuzhiyun #include <linux/spinlock.h>
12*4882a593Smuzhiyun
13*4882a593Smuzhiyun #include <asm/cpu_entry_area.h>
14*4882a593Smuzhiyun #include <asm/fixmap.h>
15*4882a593Smuzhiyun #include <asm/e820/api.h>
16*4882a593Smuzhiyun #include <asm/tlb.h>
17*4882a593Smuzhiyun #include <asm/tlbflush.h>
18*4882a593Smuzhiyun #include <asm/io.h>
19*4882a593Smuzhiyun #include <linux/vmalloc.h>
20*4882a593Smuzhiyun
21*4882a593Smuzhiyun unsigned int __VMALLOC_RESERVE = 128 << 20;
22*4882a593Smuzhiyun
23*4882a593Smuzhiyun /*
24*4882a593Smuzhiyun * Associate a virtual page frame with a given physical page frame
25*4882a593Smuzhiyun * and protection flags for that frame.
26*4882a593Smuzhiyun */
set_pte_vaddr(unsigned long vaddr,pte_t pteval)27*4882a593Smuzhiyun void set_pte_vaddr(unsigned long vaddr, pte_t pteval)
28*4882a593Smuzhiyun {
29*4882a593Smuzhiyun pgd_t *pgd;
30*4882a593Smuzhiyun p4d_t *p4d;
31*4882a593Smuzhiyun pud_t *pud;
32*4882a593Smuzhiyun pmd_t *pmd;
33*4882a593Smuzhiyun pte_t *pte;
34*4882a593Smuzhiyun
35*4882a593Smuzhiyun pgd = swapper_pg_dir + pgd_index(vaddr);
36*4882a593Smuzhiyun if (pgd_none(*pgd)) {
37*4882a593Smuzhiyun BUG();
38*4882a593Smuzhiyun return;
39*4882a593Smuzhiyun }
40*4882a593Smuzhiyun p4d = p4d_offset(pgd, vaddr);
41*4882a593Smuzhiyun if (p4d_none(*p4d)) {
42*4882a593Smuzhiyun BUG();
43*4882a593Smuzhiyun return;
44*4882a593Smuzhiyun }
45*4882a593Smuzhiyun pud = pud_offset(p4d, vaddr);
46*4882a593Smuzhiyun if (pud_none(*pud)) {
47*4882a593Smuzhiyun BUG();
48*4882a593Smuzhiyun return;
49*4882a593Smuzhiyun }
50*4882a593Smuzhiyun pmd = pmd_offset(pud, vaddr);
51*4882a593Smuzhiyun if (pmd_none(*pmd)) {
52*4882a593Smuzhiyun BUG();
53*4882a593Smuzhiyun return;
54*4882a593Smuzhiyun }
55*4882a593Smuzhiyun pte = pte_offset_kernel(pmd, vaddr);
56*4882a593Smuzhiyun if (!pte_none(pteval))
57*4882a593Smuzhiyun set_pte_at(&init_mm, vaddr, pte, pteval);
58*4882a593Smuzhiyun else
59*4882a593Smuzhiyun pte_clear(&init_mm, vaddr, pte);
60*4882a593Smuzhiyun
61*4882a593Smuzhiyun /*
62*4882a593Smuzhiyun * It's enough to flush this one mapping.
63*4882a593Smuzhiyun * (PGE mappings get flushed as well)
64*4882a593Smuzhiyun */
65*4882a593Smuzhiyun flush_tlb_one_kernel(vaddr);
66*4882a593Smuzhiyun }
67*4882a593Smuzhiyun
68*4882a593Smuzhiyun unsigned long __FIXADDR_TOP = 0xfffff000;
69*4882a593Smuzhiyun EXPORT_SYMBOL(__FIXADDR_TOP);
70*4882a593Smuzhiyun
71*4882a593Smuzhiyun /*
72*4882a593Smuzhiyun * vmalloc=size forces the vmalloc area to be exactly 'size'
73*4882a593Smuzhiyun * bytes. This can be used to increase (or decrease) the
74*4882a593Smuzhiyun * vmalloc area - the default is 128m.
75*4882a593Smuzhiyun */
parse_vmalloc(char * arg)76*4882a593Smuzhiyun static int __init parse_vmalloc(char *arg)
77*4882a593Smuzhiyun {
78*4882a593Smuzhiyun if (!arg)
79*4882a593Smuzhiyun return -EINVAL;
80*4882a593Smuzhiyun
81*4882a593Smuzhiyun /* Add VMALLOC_OFFSET to the parsed value due to vm area guard hole*/
82*4882a593Smuzhiyun __VMALLOC_RESERVE = memparse(arg, &arg) + VMALLOC_OFFSET;
83*4882a593Smuzhiyun return 0;
84*4882a593Smuzhiyun }
85*4882a593Smuzhiyun early_param("vmalloc", parse_vmalloc);
86*4882a593Smuzhiyun
87*4882a593Smuzhiyun /*
88*4882a593Smuzhiyun * reservetop=size reserves a hole at the top of the kernel address space which
89*4882a593Smuzhiyun * a hypervisor can load into later. Needed for dynamically loaded hypervisors,
90*4882a593Smuzhiyun * so relocating the fixmap can be done before paging initialization.
91*4882a593Smuzhiyun */
parse_reservetop(char * arg)92*4882a593Smuzhiyun static int __init parse_reservetop(char *arg)
93*4882a593Smuzhiyun {
94*4882a593Smuzhiyun unsigned long address;
95*4882a593Smuzhiyun
96*4882a593Smuzhiyun if (!arg)
97*4882a593Smuzhiyun return -EINVAL;
98*4882a593Smuzhiyun
99*4882a593Smuzhiyun address = memparse(arg, &arg);
100*4882a593Smuzhiyun reserve_top_address(address);
101*4882a593Smuzhiyun early_ioremap_init();
102*4882a593Smuzhiyun return 0;
103*4882a593Smuzhiyun }
104*4882a593Smuzhiyun early_param("reservetop", parse_reservetop);
105