1 /* common.c - miscellaneous shared variables and routines */
2 /*
3 * GRUB -- GRand Unified Bootloader
4 * Copyright (C) 1999,2000,2001,2002,2004 Free Software Foundation, Inc.
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
19 */
20
21 #include <shared.h>
22
23 #ifdef SUPPORT_DISKLESS
24 # define GRUB 1
25 # include <etherboot.h>
26 #endif
27
28 /*
29 * Shared BIOS/boot data.
30 */
31
32 struct multiboot_info mbi;
33 unsigned long saved_drive;
34 unsigned long saved_partition;
35 unsigned long cdrom_drive;
36 #ifndef STAGE1_5
37 unsigned long saved_mem_upper;
38
39 /* This saves the maximum size of extended memory (in KB). */
40 unsigned long extended_memory;
41 #endif
42
43 /*
44 * Error code stuff.
45 */
46
47 grub_error_t errnum = ERR_NONE;
48
49 #ifndef STAGE1_5
50
51 char *err_list[] =
52 {
53 [ERR_NONE] = 0,
54 [ERR_BAD_ARGUMENT] = "Invalid argument",
55 [ERR_BAD_FILENAME] =
56 "Filename must be either an absolute pathname or blocklist",
57 [ERR_BAD_FILETYPE] = "Bad file or directory type",
58 [ERR_BAD_GZIP_DATA] = "Bad or corrupt data while decompressing file",
59 [ERR_BAD_GZIP_HEADER] = "Bad or incompatible header in compressed file",
60 [ERR_BAD_PART_TABLE] = "Partition table invalid or corrupt",
61 [ERR_BAD_VERSION] = "Mismatched or corrupt version of stage1/stage2",
62 [ERR_BELOW_1MB] = "Loading below 1MB is not supported",
63 [ERR_BOOT_COMMAND] = "Kernel must be loaded before booting",
64 [ERR_BOOT_FAILURE] = "Unknown boot failure",
65 [ERR_BOOT_FEATURES] = "Unsupported Multiboot features requested",
66 [ERR_DEV_FORMAT] = "Unrecognized device string",
67 [ERR_DEV_NEED_INIT] = "Device not initialized yet",
68 [ERR_DEV_VALUES] = "Invalid device requested",
69 [ERR_EXEC_FORMAT] = "Invalid or unsupported executable format",
70 [ERR_FILELENGTH] =
71 "Filesystem compatibility error, cannot read whole file",
72 [ERR_FILE_NOT_FOUND] = "File not found",
73 [ERR_FSYS_CORRUPT] = "Inconsistent filesystem structure",
74 [ERR_FSYS_MOUNT] = "Cannot mount selected partition",
75 [ERR_GEOM] = "Selected cylinder exceeds maximum supported by BIOS",
76 [ERR_NEED_LX_KERNEL] = "Linux kernel must be loaded before initrd",
77 [ERR_NEED_MB_KERNEL] = "Multiboot kernel must be loaded before modules",
78 [ERR_NO_DISK] = "Selected disk does not exist",
79 [ERR_NO_DISK_SPACE] = "No spare sectors on the disk",
80 [ERR_NO_PART] = "No such partition",
81 [ERR_NUMBER_OVERFLOW] = "Overflow while parsing number",
82 [ERR_NUMBER_PARSING] = "Error while parsing number",
83 [ERR_OUTSIDE_PART] = "Attempt to access block outside partition",
84 [ERR_PRIVILEGED] = "Must be authenticated",
85 [ERR_READ] = "Disk read error",
86 [ERR_SYMLINK_LOOP] = "Too many symbolic links",
87 [ERR_UNALIGNED] = "File is not sector aligned",
88 [ERR_UNRECOGNIZED] = "Unrecognized command",
89 [ERR_WONT_FIT] = "Selected item cannot fit into memory",
90 [ERR_WRITE] = "Disk write error",
91 };
92
93
94 /* static for BIOS memory map fakery */
95 static struct AddrRangeDesc fakemap[3] =
96 {
97 {20, 0, 0, MB_ARD_MEMORY},
98 {20, 0x100000, 0, MB_ARD_MEMORY},
99 {20, 0x1000000, 0, MB_ARD_MEMORY}
100 };
101
102 /* A big problem is that the memory areas aren't guaranteed to be:
103 (1) contiguous, (2) sorted in ascending order, or (3) non-overlapping.
104 Thus this kludge. */
105 static unsigned long
mmap_avail_at(unsigned long bottom)106 mmap_avail_at (unsigned long bottom)
107 {
108 unsigned long long top;
109 unsigned long addr;
110 int cont;
111
112 top = bottom;
113 do
114 {
115 for (cont = 0, addr = mbi.mmap_addr;
116 addr < mbi.mmap_addr + mbi.mmap_length;
117 addr += *((unsigned long *) addr) + 4)
118 {
119 struct AddrRangeDesc *desc = (struct AddrRangeDesc *) addr;
120
121 if (desc->Type == MB_ARD_MEMORY
122 && desc->BaseAddr <= top
123 && desc->BaseAddr + desc->Length > top)
124 {
125 top = desc->BaseAddr + desc->Length;
126 cont++;
127 }
128 }
129 }
130 while (cont);
131
132 /* For now, GRUB assumes 32bits addresses, so... */
133 if (top > 0xFFFFFFFF)
134 top = 0xFFFFFFFF;
135
136 return (unsigned long) top - bottom;
137 }
138 #endif /* ! STAGE1_5 */
139
140 /* This queries for BIOS information. */
141 void
init_bios_info(void)142 init_bios_info (void)
143 {
144 #ifndef STAGE1_5
145 unsigned long cont, memtmp, addr;
146 int drive;
147 #endif
148
149 /*
150 * Get information from BIOS on installed RAM.
151 */
152
153 mbi.mem_lower = get_memsize (0);
154 mbi.mem_upper = get_memsize (1);
155
156 #ifndef STAGE1_5
157 /*
158 * We need to call this somewhere before trying to put data
159 * above 1 MB, since without calling it, address line 20 will be wired
160 * to 0. Not too desirable.
161 */
162
163 gateA20 (1);
164
165 /* Store the size of extended memory in EXTENDED_MEMORY, in order to
166 tell it to non-Multiboot OSes. */
167 extended_memory = mbi.mem_upper;
168
169 /*
170 * The "mbi.mem_upper" variable only recognizes upper memory in the
171 * first memory region. If there are multiple memory regions,
172 * the rest are reported to a Multiboot-compliant OS, but otherwise
173 * unused by GRUB.
174 */
175
176 addr = get_code_end ();
177 mbi.mmap_addr = addr;
178 mbi.mmap_length = 0;
179 cont = 0;
180
181 do
182 {
183 cont = get_mmap_entry ((void *) addr, cont);
184
185 /* If the returned buffer's length is zero, quit. */
186 if (! *((unsigned long *) addr))
187 break;
188
189 mbi.mmap_length += *((unsigned long *) addr) + 4;
190 addr += *((unsigned long *) addr) + 4;
191 }
192 while (cont);
193
194 if (mbi.mmap_length)
195 {
196 unsigned long long max_addr;
197
198 /*
199 * This is to get the lower memory, and upper memory (up to the
200 * first memory hole), into the "mbi.mem_{lower,upper}"
201 * elements. This is for OS's that don't care about the memory
202 * map, but might care about total RAM available.
203 */
204 mbi.mem_lower = mmap_avail_at (0) >> 10;
205 mbi.mem_upper = mmap_avail_at (0x100000) >> 10;
206
207 /* Find the maximum available address. Ignore any memory holes. */
208 for (max_addr = 0, addr = mbi.mmap_addr;
209 addr < mbi.mmap_addr + mbi.mmap_length;
210 addr += *((unsigned long *) addr) + 4)
211 {
212 struct AddrRangeDesc *desc = (struct AddrRangeDesc *) addr;
213
214 if (desc->Type == MB_ARD_MEMORY && desc->Length > 0
215 && desc->BaseAddr + desc->Length > max_addr)
216 max_addr = desc->BaseAddr + desc->Length;
217 }
218
219 extended_memory = (max_addr - 0x100000) >> 10;
220 }
221 else if ((memtmp = get_eisamemsize ()) != -1)
222 {
223 cont = memtmp & ~0xFFFF;
224 memtmp = memtmp & 0xFFFF;
225
226 if (cont != 0)
227 extended_memory = (cont >> 10) + 0x3c00;
228 else
229 extended_memory = memtmp;
230
231 if (!cont || (memtmp == 0x3c00))
232 memtmp += (cont >> 10);
233 else
234 {
235 /* XXX should I do this at all ??? */
236
237 mbi.mmap_addr = (unsigned long) fakemap;
238 mbi.mmap_length = sizeof (fakemap);
239 fakemap[0].Length = (mbi.mem_lower << 10);
240 fakemap[1].Length = (memtmp << 10);
241 fakemap[2].Length = cont;
242 }
243
244 mbi.mem_upper = memtmp;
245 }
246
247 saved_mem_upper = mbi.mem_upper;
248
249 /* Get the drive info. */
250 /* FIXME: This should be postponed until a Multiboot kernel actually
251 requires it, because this could slow down the start-up
252 unreasonably. */
253 mbi.drives_length = 0;
254 mbi.drives_addr = addr;
255
256 /* For now, GRUB doesn't probe floppies, since it is trivial to map
257 floppy drives to BIOS drives. */
258 for (drive = 0x80; drive < 0x88; drive++)
259 {
260 struct geometry geom;
261 struct drive_info *info = (struct drive_info *) addr;
262 unsigned short *port;
263
264 /* Get the geometry. This ensures that the drive is present. */
265 if (get_diskinfo (drive, &geom))
266 break;
267
268 /* Clean out the I/O map. */
269 grub_memset ((char *) io_map, 0,
270 IO_MAP_SIZE * sizeof (unsigned short));
271
272 /* Disable to probe I/O ports temporarily, because this doesn't
273 work with some BIOSes (maybe they are too buggy). */
274 #if 0
275 /* Track the int13 handler. */
276 track_int13 (drive);
277 #endif
278
279 /* Set the information. */
280 info->drive_number = drive;
281 info->drive_mode = ((geom.flags & BIOSDISK_FLAG_LBA_EXTENSION)
282 ? MB_DI_LBA_MODE : MB_DI_CHS_MODE);
283 info->drive_cylinders = geom.cylinders;
284 info->drive_heads = geom.heads;
285 info->drive_sectors = geom.sectors;
286
287 addr += sizeof (struct drive_info);
288 for (port = io_map; *port; port++, addr += sizeof (unsigned short))
289 *((unsigned short *) addr) = *port;
290
291 info->size = addr - (unsigned long) info;
292 mbi.drives_length += info->size;
293 }
294
295 /* Get the ROM configuration table by INT 15, AH=C0h. */
296 mbi.config_table = get_rom_config_table ();
297
298 /* Set the boot loader name. */
299 mbi.boot_loader_name = (unsigned long) "GNU GRUB " VERSION;
300
301 /* Get the APM BIOS table. */
302 get_apm_info ();
303 if (apm_bios_info.version)
304 mbi.apm_table = (unsigned long) &apm_bios_info;
305
306 /*
307 * Initialize other Multiboot Info flags.
308 */
309
310 mbi.flags = (MB_INFO_MEMORY | MB_INFO_CMDLINE | MB_INFO_BOOTDEV
311 | MB_INFO_DRIVE_INFO | MB_INFO_CONFIG_TABLE
312 | MB_INFO_BOOT_LOADER_NAME);
313
314 if (apm_bios_info.version)
315 mbi.flags |= MB_INFO_APM_TABLE;
316
317 #endif /* STAGE1_5 */
318
319 /* Set boot drive and partition. */
320 saved_drive = boot_drive;
321 saved_partition = install_partition;
322
323 /* Set cdrom drive. */
324 {
325 struct geometry geom;
326
327 /* Get the geometry. */
328 if (get_diskinfo (boot_drive, &geom)
329 || ! (geom.flags & BIOSDISK_FLAG_CDROM))
330 cdrom_drive = GRUB_INVALID_DRIVE;
331 else
332 cdrom_drive = boot_drive;
333 }
334
335 /* Start main routine here. */
336 cmain ();
337 }
338