1 /*
2 * Copyright (c) 1998 Michael Smith <msmith@freebsd.org>
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 */
26
27 #include <sys/cdefs.h>
28
29 /*
30 * MD primitives supporting placement of module data
31 *
32 * XXX should check load address/size against memory top.
33 */
34 #include <stand.h>
35 #include <sys/param.h>
36 #include <sys/multiboot2.h>
37 #include <machine/metadata.h>
38 #include <machine/pc/bios.h>
39 #include "libi386.h"
40 #include "btxv86.h"
41 #include "bootstrap.h"
42
43 /*
44 * Verify the address is not in use by existing modules.
45 */
46 static vm_offset_t
addr_verify(struct preloaded_file * fp,vm_offset_t addr,size_t size)47 addr_verify(struct preloaded_file *fp, vm_offset_t addr, size_t size)
48 {
49 vm_offset_t f_addr;
50
51 while (fp != NULL) {
52 f_addr = fp->f_addr;
53
54 if ((f_addr <= addr) &&
55 (f_addr + fp->f_size >= addr)) {
56 return (0);
57 }
58 if ((f_addr >= addr) && (f_addr <= addr + size)) {
59 return (0);
60 }
61 fp = fp->f_next;
62 }
63 return (addr);
64 }
65
66 /*
67 * Find smap entry above 1MB, able to contain size bytes from addr.
68 */
69 static vm_offset_t
smap_find(struct bios_smap * smap,int smaplen,vm_offset_t addr,size_t size)70 smap_find(struct bios_smap *smap, int smaplen, vm_offset_t addr, size_t size)
71 {
72 int i;
73
74 for (i = 0; i < smaplen; i++) {
75 if (smap[i].type != SMAP_TYPE_MEMORY)
76 continue;
77
78 /* We do not want address below 1MB. */
79 if (smap[i].base < 0x100000)
80 continue;
81
82 /* Do we fit into current entry? */
83 if ((smap[i].base <= addr) &&
84 (smap[i].base + smap[i].length >= addr + size)) {
85 return (addr);
86 }
87
88 /* Do we fit into new entry? */
89 if ((smap[i].base > addr) && (smap[i].length >= size)) {
90 return (smap[i].base);
91 }
92 }
93 return (0);
94 }
95
96 /*
97 * Find usable address for loading. The address for the kernel is fixed, as
98 * it is determined by kernel linker map (dboot PT_LOAD address).
99 * For modules, we need to consult smap, the module address has to be
100 * aligned to page boundary and we have to fit into smap entry.
101 */
102 vm_offset_t
i386_loadaddr(u_int type,void * data,vm_offset_t addr)103 i386_loadaddr(u_int type, void *data, vm_offset_t addr)
104 {
105 struct stat st;
106 size_t size, smaplen;
107 struct preloaded_file *fp, *mfp;
108 struct file_metadata *md;
109 struct bios_smap *smap;
110 vm_offset_t off;
111
112 /*
113 * For now, assume we have memory for the kernel, the
114 * required map is [1MB..) This assumption should be safe with x86 BIOS.
115 */
116 if (type == LOAD_KERN)
117 return (addr);
118
119 if (addr == 0)
120 return (addr); /* nothing to do */
121
122 if (type == LOAD_ELF)
123 return (0); /* not supported */
124
125 if (type == LOAD_MEM) {
126 size = *(size_t *)data;
127 } else {
128 stat(data, &st);
129 size = st.st_size;
130 }
131
132 /*
133 * Find our kernel, from it we will find the smap and the list of
134 * loaded modules.
135 */
136 fp = file_findfile(NULL, NULL);
137 if (fp == NULL)
138 return (0);
139 md = file_findmetadata(fp, MODINFOMD_SMAP);
140 if (md == NULL)
141 return (0);
142
143 smap = (struct bios_smap *)md->md_data;
144 smaplen = md->md_size / sizeof(struct bios_smap);
145
146 /* Start from the end of the kernel. */
147 mfp = fp;
148 do {
149 if (mfp == NULL) {
150 off = roundup2(addr + 1, MULTIBOOT_MOD_ALIGN);
151 } else {
152 off = roundup2(mfp->f_addr + mfp->f_size + 1,
153 MULTIBOOT_MOD_ALIGN);
154 }
155 off = smap_find(smap, smaplen, off, size);
156 off = addr_verify(fp, off, size);
157 if (off != 0)
158 break;
159
160 if (mfp == NULL)
161 break;
162 mfp = mfp->f_next;
163 } while (off == 0);
164
165 return (off);
166 }
167
168 ssize_t
i386_copyin(const void * src,vm_offset_t dest,const size_t len)169 i386_copyin(const void *src, vm_offset_t dest, const size_t len)
170 {
171 if (dest + len >= memtop) {
172 errno = EFBIG;
173 return (-1);
174 }
175
176 bcopy(src, PTOV(dest), len);
177 return (len);
178 }
179
180 ssize_t
i386_copyout(const vm_offset_t src,void * dest,const size_t len)181 i386_copyout(const vm_offset_t src, void *dest, const size_t len)
182 {
183 if (src + len >= memtop) {
184 errno = EFBIG;
185 return (-1);
186 }
187
188 bcopy(PTOV(src), dest, len);
189 return (len);
190 }
191
192
193 ssize_t
i386_readin(const int fd,vm_offset_t dest,const size_t len)194 i386_readin(const int fd, vm_offset_t dest, const size_t len)
195 {
196 if (dest + len >= memtop_copyin) {
197 errno = EFBIG;
198 return (-1);
199 }
200
201 return (read(fd, PTOV(dest), len));
202 }
203