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1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright (C) 2000 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
4 */
5
6#include <linux/module.h>
7#include <linux/memblock.h>
8#include <linux/mm.h>
9#include <linux/pfn.h>
10#include <asm/page.h>
11#include <asm/sections.h>
12#include <as-layout.h>
13#include <init.h>
14#include <kern.h>
15#include <kern_util.h>
16#include <mem_user.h>
17#include <os.h>
18
19static int physmem_fd = -1;
20
21/* Changed during early boot */
22unsigned long high_physmem;
23EXPORT_SYMBOL(high_physmem);
24
25void __init mem_total_pages(unsigned long physmem, unsigned long iomem)
26{
27 unsigned long phys_pages, iomem_pages, total_pages;
28
29 phys_pages = physmem >> PAGE_SHIFT;
30 iomem_pages = iomem >> PAGE_SHIFT;
31
32 total_pages = phys_pages + iomem_pages;
33
34 max_mapnr = total_pages;
35}
36
37void map_memory(unsigned long virt, unsigned long phys, unsigned long len,
38 int r, int w, int x)
39{
40 __u64 offset;
41 int fd, err;
42
43 fd = phys_mapping(phys, &offset);
44 err = os_map_memory((void *) virt, fd, offset, len, r, w, x);
45 if (err) {
46 if (err == -ENOMEM)
47 printk(KERN_ERR "try increasing the host's "
48 "/proc/sys/vm/max_map_count to <physical "
49 "memory size>/4096\n");
50 panic("map_memory(0x%lx, %d, 0x%llx, %ld, %d, %d, %d) failed, "
51 "err = %d\n", virt, fd, offset, len, r, w, x, err);
52 }
53}
54
55/**
56 * setup_physmem() - Setup physical memory for UML
57 * @start: Start address of the physical kernel memory,
58 * i.e start address of the executable image.
59 * @reserve_end: end address of the physical kernel memory.
60 * @len: Length of total physical memory that should be mapped/made
61 * available, in bytes.
62 *
63 * Creates an unlinked temporary file of size (len) and memory maps
64 * it on the last executable image address (uml_reserved).
65 *
66 * The offset is needed as the length of the total physical memory
67 * (len) includes the size of the memory used be the executable image,
68 * but the mapped-to address is the last address of the executable image
69 * (uml_reserved == end address of executable image).
70 *
71 * The memory mapped memory of the temporary file is used as backing memory
72 * of all user space processes/kernel tasks.
73 */
74void __init setup_physmem(unsigned long start, unsigned long reserve_end,
75 unsigned long len)
76{
77 unsigned long reserve = reserve_end - start;
78 unsigned long map_size = len - reserve;
79 int err;
80
81 if (len <= reserve) {
82 os_warn("Too few physical memory! Needed=%lu, given=%lu\n",
83 reserve, len);
84 exit(1);
85 }
86
87 physmem_fd = create_mem_file(len);
88
89 err = os_map_memory((void *) reserve_end, physmem_fd, reserve,
90 map_size, 1, 1, 1);
91 if (err < 0) {
92 os_warn("setup_physmem - mapping %lu bytes of memory at 0x%p "
93 "failed - errno = %d\n", map_size,
94 (void *) reserve_end, err);
95 exit(1);
96 }
97
98 /*
99 * Special kludge - This page will be mapped in to userspace processes
100 * from physmem_fd, so it needs to be written out there.
101 */
102 os_seek_file(physmem_fd, __pa(__syscall_stub_start));
103 os_write_file(physmem_fd, __syscall_stub_start, PAGE_SIZE);
104
105 memblock_add(__pa(start), len);
106 memblock_reserve(__pa(start), reserve);
107
108 min_low_pfn = PFN_UP(__pa(reserve_end));
109 max_low_pfn = min_low_pfn + (map_size >> PAGE_SHIFT);
110}
111
112int phys_mapping(unsigned long phys, unsigned long long *offset_out)
113{
114 int fd = -1;
115
116 if (phys < physmem_size) {
117 fd = physmem_fd;
118 *offset_out = phys;
119 }
120 else if (phys < __pa(end_iomem)) {
121 struct iomem_region *region = iomem_regions;
122
123 while (region != NULL) {
124 if ((phys >= region->phys) &&
125 (phys < region->phys + region->size)) {
126 fd = region->fd;
127 *offset_out = phys - region->phys;
128 break;
129 }
130 region = region->next;
131 }
132 }
133
134 return fd;
135}
136EXPORT_SYMBOL(phys_mapping);
137
138static int __init uml_mem_setup(char *line, int *add)
139{
140 char *retptr;
141
142 *add = 0;
143 physmem_size = memparse(line,&retptr);
144 return 0;
145}
146__uml_setup("mem=", uml_mem_setup,
147"mem=<Amount of desired ram>\n"
148" This controls how much \"physical\" memory the kernel allocates\n"
149" for the system. The size is specified as a number followed by\n"
150" one of 'k', 'K', 'm', 'M', which have the obvious meanings.\n"
151" This is not related to the amount of memory in the host. It can\n"
152" be more, and the excess, if it's ever used, will just be swapped out.\n"
153" Example: mem=64M\n\n"
154);
155
156__uml_setup("iomem=", parse_iomem,
157"iomem=<name>,<file>\n"
158" Configure <file> as an IO memory region named <name>.\n\n"
159);
160
161/*
162 * This list is constructed in parse_iomem and addresses filled in
163 * setup_iomem, both of which run during early boot. Afterwards, it's
164 * unchanged.
165 */
166struct iomem_region *iomem_regions;
167
168/* Initialized in parse_iomem and unchanged thereafter */
169int iomem_size;
170
171unsigned long find_iomem(char *driver, unsigned long *len_out)
172{
173 struct iomem_region *region = iomem_regions;
174
175 while (region != NULL) {
176 if (!strcmp(region->driver, driver)) {
177 *len_out = region->size;
178 return region->virt;
179 }
180
181 region = region->next;
182 }
183
184 return 0;
185}
186EXPORT_SYMBOL(find_iomem);
187
188static int setup_iomem(void)
189{
190 struct iomem_region *region = iomem_regions;
191 unsigned long iomem_start = high_physmem + PAGE_SIZE;
192 int err;
193
194 while (region != NULL) {
195 err = os_map_memory((void *) iomem_start, region->fd, 0,
196 region->size, 1, 1, 0);
197 if (err)
198 printk(KERN_ERR "Mapping iomem region for driver '%s' "
199 "failed, errno = %d\n", region->driver, -err);
200 else {
201 region->virt = iomem_start;
202 region->phys = __pa(region->virt);
203 }
204
205 iomem_start += region->size + PAGE_SIZE;
206 region = region->next;
207 }
208
209 return 0;
210}
211
212__initcall(setup_iomem);
1/*
2 * Copyright (C) 2000 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
3 * Licensed under the GPL
4 */
5
6#include <linux/module.h>
7#include <linux/bootmem.h>
8#include <linux/mm.h>
9#include <linux/pfn.h>
10#include <asm/page.h>
11#include <as-layout.h>
12#include <init.h>
13#include <kern.h>
14#include <mem_user.h>
15#include <os.h>
16
17static int physmem_fd = -1;
18
19/* Changed during early boot */
20unsigned long high_physmem;
21EXPORT_SYMBOL(high_physmem);
22
23extern unsigned long long physmem_size;
24
25int __init init_maps(unsigned long physmem, unsigned long iomem,
26 unsigned long highmem)
27{
28 struct page *p, *map;
29 unsigned long phys_len, phys_pages, highmem_len, highmem_pages;
30 unsigned long iomem_len, iomem_pages, total_len, total_pages;
31 int i;
32
33 phys_pages = physmem >> PAGE_SHIFT;
34 phys_len = phys_pages * sizeof(struct page);
35
36 iomem_pages = iomem >> PAGE_SHIFT;
37 iomem_len = iomem_pages * sizeof(struct page);
38
39 highmem_pages = highmem >> PAGE_SHIFT;
40 highmem_len = highmem_pages * sizeof(struct page);
41
42 total_pages = phys_pages + iomem_pages + highmem_pages;
43 total_len = phys_len + iomem_len + highmem_len;
44
45 map = alloc_bootmem_low_pages(total_len);
46 if (map == NULL)
47 return -ENOMEM;
48
49 for (i = 0; i < total_pages; i++) {
50 p = &map[i];
51 memset(p, 0, sizeof(struct page));
52 SetPageReserved(p);
53 INIT_LIST_HEAD(&p->lru);
54 }
55
56 max_mapnr = total_pages;
57 return 0;
58}
59
60void map_memory(unsigned long virt, unsigned long phys, unsigned long len,
61 int r, int w, int x)
62{
63 __u64 offset;
64 int fd, err;
65
66 fd = phys_mapping(phys, &offset);
67 err = os_map_memory((void *) virt, fd, offset, len, r, w, x);
68 if (err) {
69 if (err == -ENOMEM)
70 printk(KERN_ERR "try increasing the host's "
71 "/proc/sys/vm/max_map_count to <physical "
72 "memory size>/4096\n");
73 panic("map_memory(0x%lx, %d, 0x%llx, %ld, %d, %d, %d) failed, "
74 "err = %d\n", virt, fd, offset, len, r, w, x, err);
75 }
76}
77
78extern int __syscall_stub_start;
79
80void __init setup_physmem(unsigned long start, unsigned long reserve_end,
81 unsigned long len, unsigned long long highmem)
82{
83 unsigned long reserve = reserve_end - start;
84 int pfn = PFN_UP(__pa(reserve_end));
85 int delta = (len - reserve) >> PAGE_SHIFT;
86 int err, offset, bootmap_size;
87
88 physmem_fd = create_mem_file(len + highmem);
89
90 offset = uml_reserved - uml_physmem;
91 err = os_map_memory((void *) uml_reserved, physmem_fd, offset,
92 len - offset, 1, 1, 1);
93 if (err < 0) {
94 printf("setup_physmem - mapping %ld bytes of memory at 0x%p "
95 "failed - errno = %d\n", len - offset,
96 (void *) uml_reserved, err);
97 exit(1);
98 }
99
100 /*
101 * Special kludge - This page will be mapped in to userspace processes
102 * from physmem_fd, so it needs to be written out there.
103 */
104 os_seek_file(physmem_fd, __pa(&__syscall_stub_start));
105 os_write_file(physmem_fd, &__syscall_stub_start, PAGE_SIZE);
106 os_fsync_file(physmem_fd);
107
108 bootmap_size = init_bootmem(pfn, pfn + delta);
109 free_bootmem(__pa(reserve_end) + bootmap_size,
110 len - bootmap_size - reserve);
111}
112
113int phys_mapping(unsigned long phys, unsigned long long *offset_out)
114{
115 int fd = -1;
116
117 if (phys < physmem_size) {
118 fd = physmem_fd;
119 *offset_out = phys;
120 }
121 else if (phys < __pa(end_iomem)) {
122 struct iomem_region *region = iomem_regions;
123
124 while (region != NULL) {
125 if ((phys >= region->phys) &&
126 (phys < region->phys + region->size)) {
127 fd = region->fd;
128 *offset_out = phys - region->phys;
129 break;
130 }
131 region = region->next;
132 }
133 }
134 else if (phys < __pa(end_iomem) + highmem) {
135 fd = physmem_fd;
136 *offset_out = phys - iomem_size;
137 }
138
139 return fd;
140}
141
142static int __init uml_mem_setup(char *line, int *add)
143{
144 char *retptr;
145 physmem_size = memparse(line,&retptr);
146 return 0;
147}
148__uml_setup("mem=", uml_mem_setup,
149"mem=<Amount of desired ram>\n"
150" This controls how much \"physical\" memory the kernel allocates\n"
151" for the system. The size is specified as a number followed by\n"
152" one of 'k', 'K', 'm', 'M', which have the obvious meanings.\n"
153" This is not related to the amount of memory in the host. It can\n"
154" be more, and the excess, if it's ever used, will just be swapped out.\n"
155" Example: mem=64M\n\n"
156);
157
158extern int __init parse_iomem(char *str, int *add);
159
160__uml_setup("iomem=", parse_iomem,
161"iomem=<name>,<file>\n"
162" Configure <file> as an IO memory region named <name>.\n\n"
163);
164
165/*
166 * This list is constructed in parse_iomem and addresses filled in in
167 * setup_iomem, both of which run during early boot. Afterwards, it's
168 * unchanged.
169 */
170struct iomem_region *iomem_regions;
171
172/* Initialized in parse_iomem and unchanged thereafter */
173int iomem_size;
174
175unsigned long find_iomem(char *driver, unsigned long *len_out)
176{
177 struct iomem_region *region = iomem_regions;
178
179 while (region != NULL) {
180 if (!strcmp(region->driver, driver)) {
181 *len_out = region->size;
182 return region->virt;
183 }
184
185 region = region->next;
186 }
187
188 return 0;
189}
190EXPORT_SYMBOL(find_iomem);
191
192static int setup_iomem(void)
193{
194 struct iomem_region *region = iomem_regions;
195 unsigned long iomem_start = high_physmem + PAGE_SIZE;
196 int err;
197
198 while (region != NULL) {
199 err = os_map_memory((void *) iomem_start, region->fd, 0,
200 region->size, 1, 1, 0);
201 if (err)
202 printk(KERN_ERR "Mapping iomem region for driver '%s' "
203 "failed, errno = %d\n", region->driver, -err);
204 else {
205 region->virt = iomem_start;
206 region->phys = __pa(region->virt);
207 }
208
209 iomem_start += region->size + PAGE_SIZE;
210 region = region->next;
211 }
212
213 return 0;
214}
215
216__initcall(setup_iomem);