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
17 static int physmem_fd = -1;
18
19 /* Changed during early boot */
20 unsigned long high_physmem;
21 EXPORT_SYMBOL(high_physmem);
22
23 extern unsigned long long physmem_size;
24
mem_total_pages(unsigned long physmem,unsigned long iomem,unsigned long highmem)25 void __init mem_total_pages(unsigned long physmem, unsigned long iomem,
26 unsigned long highmem)
27 {
28 unsigned long phys_pages, highmem_pages;
29 unsigned long iomem_pages, total_pages;
30
31 phys_pages = physmem >> PAGE_SHIFT;
32 iomem_pages = iomem >> PAGE_SHIFT;
33 highmem_pages = highmem >> PAGE_SHIFT;
34
35 total_pages = phys_pages + iomem_pages + highmem_pages;
36
37 max_mapnr = total_pages;
38 }
39
map_memory(unsigned long virt,unsigned long phys,unsigned long len,int r,int w,int x)40 void map_memory(unsigned long virt, unsigned long phys, unsigned long len,
41 int r, int w, int x)
42 {
43 __u64 offset;
44 int fd, err;
45
46 fd = phys_mapping(phys, &offset);
47 err = os_map_memory((void *) virt, fd, offset, len, r, w, x);
48 if (err) {
49 if (err == -ENOMEM)
50 printk(KERN_ERR "try increasing the host's "
51 "/proc/sys/vm/max_map_count to <physical "
52 "memory size>/4096\n");
53 panic("map_memory(0x%lx, %d, 0x%llx, %ld, %d, %d, %d) failed, "
54 "err = %d\n", virt, fd, offset, len, r, w, x, err);
55 }
56 }
57
58 extern int __syscall_stub_start;
59
setup_physmem(unsigned long start,unsigned long reserve_end,unsigned long len,unsigned long long highmem)60 void __init setup_physmem(unsigned long start, unsigned long reserve_end,
61 unsigned long len, unsigned long long highmem)
62 {
63 unsigned long reserve = reserve_end - start;
64 int pfn = PFN_UP(__pa(reserve_end));
65 int delta = (len - reserve) >> PAGE_SHIFT;
66 int err, offset, bootmap_size;
67
68 physmem_fd = create_mem_file(len + highmem);
69
70 offset = uml_reserved - uml_physmem;
71 err = os_map_memory((void *) uml_reserved, physmem_fd, offset,
72 len - offset, 1, 1, 1);
73 if (err < 0) {
74 printf("setup_physmem - mapping %ld bytes of memory at 0x%p "
75 "failed - errno = %d\n", len - offset,
76 (void *) uml_reserved, err);
77 exit(1);
78 }
79
80 /*
81 * Special kludge - This page will be mapped in to userspace processes
82 * from physmem_fd, so it needs to be written out there.
83 */
84 os_seek_file(physmem_fd, __pa(&__syscall_stub_start));
85 os_write_file(physmem_fd, &__syscall_stub_start, PAGE_SIZE);
86 os_fsync_file(physmem_fd);
87
88 bootmap_size = init_bootmem(pfn, pfn + delta);
89 free_bootmem(__pa(reserve_end) + bootmap_size,
90 len - bootmap_size - reserve);
91 }
92
phys_mapping(unsigned long phys,unsigned long long * offset_out)93 int phys_mapping(unsigned long phys, unsigned long long *offset_out)
94 {
95 int fd = -1;
96
97 if (phys < physmem_size) {
98 fd = physmem_fd;
99 *offset_out = phys;
100 }
101 else if (phys < __pa(end_iomem)) {
102 struct iomem_region *region = iomem_regions;
103
104 while (region != NULL) {
105 if ((phys >= region->phys) &&
106 (phys < region->phys + region->size)) {
107 fd = region->fd;
108 *offset_out = phys - region->phys;
109 break;
110 }
111 region = region->next;
112 }
113 }
114 else if (phys < __pa(end_iomem) + highmem) {
115 fd = physmem_fd;
116 *offset_out = phys - iomem_size;
117 }
118
119 return fd;
120 }
121
uml_mem_setup(char * line,int * add)122 static int __init uml_mem_setup(char *line, int *add)
123 {
124 char *retptr;
125 physmem_size = memparse(line,&retptr);
126 return 0;
127 }
128 __uml_setup("mem=", uml_mem_setup,
129 "mem=<Amount of desired ram>\n"
130 " This controls how much \"physical\" memory the kernel allocates\n"
131 " for the system. The size is specified as a number followed by\n"
132 " one of 'k', 'K', 'm', 'M', which have the obvious meanings.\n"
133 " This is not related to the amount of memory in the host. It can\n"
134 " be more, and the excess, if it's ever used, will just be swapped out.\n"
135 " Example: mem=64M\n\n"
136 );
137
138 extern int __init parse_iomem(char *str, int *add);
139
140 __uml_setup("iomem=", parse_iomem,
141 "iomem=<name>,<file>\n"
142 " Configure <file> as an IO memory region named <name>.\n\n"
143 );
144
145 /*
146 * This list is constructed in parse_iomem and addresses filled in in
147 * setup_iomem, both of which run during early boot. Afterwards, it's
148 * unchanged.
149 */
150 struct iomem_region *iomem_regions;
151
152 /* Initialized in parse_iomem and unchanged thereafter */
153 int iomem_size;
154
find_iomem(char * driver,unsigned long * len_out)155 unsigned long find_iomem(char *driver, unsigned long *len_out)
156 {
157 struct iomem_region *region = iomem_regions;
158
159 while (region != NULL) {
160 if (!strcmp(region->driver, driver)) {
161 *len_out = region->size;
162 return region->virt;
163 }
164
165 region = region->next;
166 }
167
168 return 0;
169 }
170 EXPORT_SYMBOL(find_iomem);
171
setup_iomem(void)172 static int setup_iomem(void)
173 {
174 struct iomem_region *region = iomem_regions;
175 unsigned long iomem_start = high_physmem + PAGE_SIZE;
176 int err;
177
178 while (region != NULL) {
179 err = os_map_memory((void *) iomem_start, region->fd, 0,
180 region->size, 1, 1, 0);
181 if (err)
182 printk(KERN_ERR "Mapping iomem region for driver '%s' "
183 "failed, errno = %d\n", region->driver, -err);
184 else {
185 region->virt = iomem_start;
186 region->phys = __pa(region->virt);
187 }
188
189 iomem_start += region->size + PAGE_SIZE;
190 region = region->next;
191 }
192
193 return 0;
194 }
195
196 __initcall(setup_iomem);
197