1 /*
2 * QEMU PC System Emulator
3 *
4 * Copyright (c) 2003-2004 Fabrice Bellard
5 *
6 * Permission is hereby granted, free of charge, to any person obtaining a copy
7 * of this software and associated documentation files (the "Software"), to deal
8 * in the Software without restriction, including without limitation the rights
9 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
10 * copies of the Software, and to permit persons to whom the Software is
11 * furnished to do so, subject to the following conditions:
12 *
13 * The above copyright notice and this permission notice shall be included in
14 * all copies or substantial portions of the Software.
15 *
16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
19 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
21 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
22 * THE SOFTWARE.
23 */
24
25 #include "qemu/osdep.h"
26 #include "qemu/option.h"
27 #include "cpu.h"
28 #include "hw/nvram/fw_cfg.h"
29 #include "multiboot.h"
30 #include "hw/loader.h"
31 #include "elf.h"
32 #include "exec/target_page.h"
33 #include "system/system.h"
34 #include "qemu/error-report.h"
35
36 /* Show multiboot debug output */
37 //#define DEBUG_MULTIBOOT
38
39 #ifdef DEBUG_MULTIBOOT
40 #define mb_debug(a...) error_report(a)
41 #else
42 #define mb_debug(a...)
43 #endif
44
45 #define MULTIBOOT_STRUCT_ADDR 0x9000
46
47 #if MULTIBOOT_STRUCT_ADDR > 0xf0000
48 #error multiboot struct needs to fit in 16 bit real mode
49 #endif
50
51 enum {
52 /* Multiboot info */
53 MBI_FLAGS = 0,
54 MBI_MEM_LOWER = 4,
55 MBI_MEM_UPPER = 8,
56 MBI_BOOT_DEVICE = 12,
57 MBI_CMDLINE = 16,
58 MBI_MODS_COUNT = 20,
59 MBI_MODS_ADDR = 24,
60 MBI_MMAP_ADDR = 48,
61 MBI_BOOTLOADER = 64,
62
63 MBI_SIZE = 88,
64
65 /* Multiboot modules */
66 MB_MOD_START = 0,
67 MB_MOD_END = 4,
68 MB_MOD_CMDLINE = 8,
69
70 MB_MOD_SIZE = 16,
71
72 /* Region offsets */
73 ADDR_E820_MAP = MULTIBOOT_STRUCT_ADDR + 0,
74 ADDR_MBI = ADDR_E820_MAP + 0x500,
75
76 /* Multiboot flags */
77 MULTIBOOT_FLAGS_MEMORY = 1 << 0,
78 MULTIBOOT_FLAGS_BOOT_DEVICE = 1 << 1,
79 MULTIBOOT_FLAGS_CMDLINE = 1 << 2,
80 MULTIBOOT_FLAGS_MODULES = 1 << 3,
81 MULTIBOOT_FLAGS_MMAP = 1 << 6,
82 MULTIBOOT_FLAGS_BOOTLOADER = 1 << 9,
83 };
84
85 typedef struct {
86 /* buffer holding kernel, cmdlines and mb_infos */
87 void *mb_buf;
88 /* address in target */
89 hwaddr mb_buf_phys;
90 /* size of mb_buf in bytes */
91 unsigned mb_buf_size;
92 /* offset of mb-info's in bytes */
93 hwaddr offset_mbinfo;
94 /* offset in buffer for cmdlines in bytes */
95 hwaddr offset_cmdlines;
96 /* offset in buffer for bootloader name in bytes */
97 hwaddr offset_bootloader;
98 /* offset of modules in bytes */
99 hwaddr offset_mods;
100 /* available slots for mb modules infos */
101 int mb_mods_avail;
102 /* currently used slots of mb modules */
103 int mb_mods_count;
104 } MultibootState;
105
106 const char *bootloader_name = "qemu";
107
mb_add_cmdline(MultibootState * s,const char * cmdline)108 static uint32_t mb_add_cmdline(MultibootState *s, const char *cmdline)
109 {
110 hwaddr p = s->offset_cmdlines;
111 char *b = (char *)s->mb_buf + p;
112
113 memcpy(b, cmdline, strlen(cmdline) + 1);
114 s->offset_cmdlines += strlen(b) + 1;
115 return s->mb_buf_phys + p;
116 }
117
mb_add_bootloader(MultibootState * s,const char * bootloader)118 static uint32_t mb_add_bootloader(MultibootState *s, const char *bootloader)
119 {
120 hwaddr p = s->offset_bootloader;
121 char *b = (char *)s->mb_buf + p;
122
123 memcpy(b, bootloader, strlen(bootloader) + 1);
124 s->offset_bootloader += strlen(b) + 1;
125 return s->mb_buf_phys + p;
126 }
127
mb_add_mod(MultibootState * s,hwaddr start,hwaddr end,hwaddr cmdline_phys)128 static void mb_add_mod(MultibootState *s,
129 hwaddr start, hwaddr end,
130 hwaddr cmdline_phys)
131 {
132 char *p;
133 assert(s->mb_mods_count < s->mb_mods_avail);
134
135 p = (char *)s->mb_buf + s->offset_mbinfo + MB_MOD_SIZE * s->mb_mods_count;
136
137 stl_le_p(p + MB_MOD_START, start);
138 stl_le_p(p + MB_MOD_END, end);
139 stl_le_p(p + MB_MOD_CMDLINE, cmdline_phys);
140
141 mb_debug("mod%02d: "HWADDR_FMT_plx" - "HWADDR_FMT_plx,
142 s->mb_mods_count, start, end);
143
144 s->mb_mods_count++;
145 }
146
load_multiboot(X86MachineState * x86ms,FWCfgState * fw_cfg,FILE * f,const char * kernel_filename,const char * initrd_filename,const char * kernel_cmdline,int kernel_file_size,uint8_t * header)147 int load_multiboot(X86MachineState *x86ms,
148 FWCfgState *fw_cfg,
149 FILE *f,
150 const char *kernel_filename,
151 const char *initrd_filename,
152 const char *kernel_cmdline,
153 int kernel_file_size,
154 uint8_t *header)
155 {
156 bool multiboot_dma_enabled = X86_MACHINE_GET_CLASS(x86ms)->fwcfg_dma_enabled;
157 int i, is_multiboot = 0;
158 uint32_t flags = 0;
159 uint32_t mh_entry_addr;
160 uint32_t mh_load_addr;
161 uint32_t mb_kernel_size;
162 MultibootState mbs;
163 uint8_t bootinfo[MBI_SIZE];
164 uint8_t *mb_bootinfo_data;
165 uint32_t cmdline_len;
166 GList *mods = NULL;
167 g_autofree char *kcmdline = NULL;
168
169 /* Ok, let's see if it is a multiboot image.
170 The header is 12x32bit long, so the latest entry may be 8192 - 48. */
171 for (i = 0; i < (8192 - 48); i += 4) {
172 if (ldl_le_p(header + i) == 0x1BADB002) {
173 uint32_t checksum = ldl_le_p(header + i + 8);
174 flags = ldl_le_p(header + i + 4);
175 checksum += flags;
176 checksum += (uint32_t)0x1BADB002;
177 if (!checksum) {
178 is_multiboot = 1;
179 break;
180 }
181 }
182 }
183
184 if (!is_multiboot)
185 return 0; /* no multiboot */
186
187 mb_debug("I believe we found a multiboot image!");
188 memset(bootinfo, 0, sizeof(bootinfo));
189 memset(&mbs, 0, sizeof(mbs));
190
191 if (flags & 0x00000004) { /* MULTIBOOT_HEADER_HAS_VBE */
192 error_report("multiboot knows VBE. we don't");
193 }
194 if (!(flags & 0x00010000)) { /* MULTIBOOT_HEADER_HAS_ADDR */
195 uint64_t elf_entry;
196 uint64_t elf_low, elf_high;
197 int kernel_size;
198 fclose(f);
199
200 if (((struct elf64_hdr*)header)->e_machine == EM_X86_64) {
201 error_report("Cannot load x86-64 image, give a 32bit one.");
202 exit(1);
203 }
204
205 kernel_size = load_elf(kernel_filename, NULL, NULL, NULL, &elf_entry,
206 &elf_low, &elf_high, NULL,
207 ELFDATA2LSB, I386_ELF_MACHINE, 0, 0);
208 if (kernel_size < 0) {
209 error_report("Error while loading elf kernel");
210 exit(1);
211 }
212 mh_load_addr = elf_low;
213 mb_kernel_size = elf_high - elf_low;
214 mh_entry_addr = elf_entry;
215
216 mbs.mb_buf = g_malloc(mb_kernel_size);
217 if (rom_copy(mbs.mb_buf, mh_load_addr, mb_kernel_size) != mb_kernel_size) {
218 error_report("Error while fetching elf kernel from rom");
219 exit(1);
220 }
221
222 mb_debug("loading multiboot-elf kernel "
223 "(%#x bytes) with entry %#zx",
224 mb_kernel_size, (size_t)mh_entry_addr);
225 } else {
226 /* Valid if mh_flags sets MULTIBOOT_HEADER_HAS_ADDR. */
227 uint32_t mh_header_addr = ldl_le_p(header + i + 12);
228 uint32_t mh_load_end_addr = ldl_le_p(header + i + 20);
229 uint32_t mh_bss_end_addr = ldl_le_p(header + i + 24);
230
231 mh_load_addr = ldl_le_p(header + i + 16);
232 if (mh_header_addr < mh_load_addr) {
233 error_report("invalid load_addr address");
234 exit(1);
235 }
236 if (mh_header_addr - mh_load_addr > i) {
237 error_report("invalid header_addr address");
238 exit(1);
239 }
240
241 uint32_t mb_kernel_text_offset = i - (mh_header_addr - mh_load_addr);
242 uint32_t mb_load_size = 0;
243 mh_entry_addr = ldl_le_p(header + i + 28);
244
245 if (mh_load_end_addr) {
246 if (mh_load_end_addr < mh_load_addr) {
247 error_report("invalid load_end_addr address");
248 exit(1);
249 }
250 mb_load_size = mh_load_end_addr - mh_load_addr;
251 } else {
252 if (kernel_file_size < mb_kernel_text_offset) {
253 error_report("invalid kernel_file_size");
254 exit(1);
255 }
256 mb_load_size = kernel_file_size - mb_kernel_text_offset;
257 }
258 if (mb_load_size > UINT32_MAX - mh_load_addr) {
259 error_report("kernel does not fit in address space");
260 exit(1);
261 }
262 if (mh_bss_end_addr) {
263 if (mh_bss_end_addr < (mh_load_addr + mb_load_size)) {
264 error_report("invalid bss_end_addr address");
265 exit(1);
266 }
267 mb_kernel_size = mh_bss_end_addr - mh_load_addr;
268 } else {
269 mb_kernel_size = mb_load_size;
270 }
271
272 mb_debug("multiboot: header_addr = %#x", mh_header_addr);
273 mb_debug("multiboot: load_addr = %#x", mh_load_addr);
274 mb_debug("multiboot: load_end_addr = %#x", mh_load_end_addr);
275 mb_debug("multiboot: bss_end_addr = %#x", mh_bss_end_addr);
276 mb_debug("loading multiboot kernel (%#x bytes) at %#x",
277 mb_load_size, mh_load_addr);
278
279 mbs.mb_buf = g_malloc(mb_kernel_size);
280 fseek(f, mb_kernel_text_offset, SEEK_SET);
281 if (fread(mbs.mb_buf, 1, mb_load_size, f) != mb_load_size) {
282 error_report("fread() failed");
283 exit(1);
284 }
285 memset(mbs.mb_buf + mb_load_size, 0, mb_kernel_size - mb_load_size);
286 fclose(f);
287 }
288
289 mbs.mb_buf_phys = mh_load_addr;
290
291 mbs.mb_buf_size = TARGET_PAGE_ALIGN(mb_kernel_size);
292 mbs.offset_mbinfo = mbs.mb_buf_size;
293
294 /* Calculate space for cmdlines, bootloader name, and mb_mods */
295 cmdline_len = strlen(kernel_filename) + 1;
296 cmdline_len += strlen(kernel_cmdline) + 1;
297 if (initrd_filename) {
298 const char *r = initrd_filename;
299 cmdline_len += strlen(initrd_filename) + 1;
300 while (*r) {
301 char *value;
302 r = get_opt_value(r, &value);
303 mbs.mb_mods_avail++;
304 mods = g_list_append(mods, value);
305 if (*r) {
306 r++;
307 }
308 }
309 }
310
311 mbs.mb_buf_size += cmdline_len;
312 mbs.mb_buf_size += MB_MOD_SIZE * mbs.mb_mods_avail;
313 mbs.mb_buf_size += strlen(bootloader_name) + 1;
314
315 mbs.mb_buf_size = TARGET_PAGE_ALIGN(mbs.mb_buf_size);
316
317 /* enlarge mb_buf to hold cmdlines, bootloader, mb-info structs */
318 mbs.mb_buf = g_realloc(mbs.mb_buf, mbs.mb_buf_size);
319 mbs.offset_cmdlines = mbs.offset_mbinfo + mbs.mb_mods_avail * MB_MOD_SIZE;
320 mbs.offset_bootloader = mbs.offset_cmdlines + cmdline_len;
321
322 if (mods) {
323 GList *tmpl = mods;
324 mbs.offset_mods = mbs.mb_buf_size;
325
326 while (tmpl) {
327 char *next_space;
328 int mb_mod_length;
329 uint32_t offs = mbs.mb_buf_size;
330 char *one_file = tmpl->data;
331
332 /* if a space comes after the module filename, treat everything
333 after that as parameters */
334 hwaddr c = mb_add_cmdline(&mbs, one_file);
335 next_space = strchr(one_file, ' ');
336 if (next_space) {
337 *next_space = '\0';
338 }
339 mb_debug("multiboot loading module: %s", one_file);
340 mb_mod_length = get_image_size(one_file);
341 if (mb_mod_length < 0) {
342 error_report("Failed to open file '%s'", one_file);
343 exit(1);
344 }
345
346 mbs.mb_buf_size = TARGET_PAGE_ALIGN(mb_mod_length + mbs.mb_buf_size);
347 mbs.mb_buf = g_realloc(mbs.mb_buf, mbs.mb_buf_size);
348
349 if (load_image_size(one_file, (unsigned char *)mbs.mb_buf + offs,
350 mbs.mb_buf_size - offs) < 0) {
351 error_report("Error loading file '%s'", one_file);
352 exit(1);
353 }
354 mb_add_mod(&mbs, mbs.mb_buf_phys + offs,
355 mbs.mb_buf_phys + offs + mb_mod_length, c);
356
357 mb_debug("mod_start: %p\nmod_end: %p\n cmdline: "HWADDR_FMT_plx,
358 (char *)mbs.mb_buf + offs,
359 (char *)mbs.mb_buf + offs + mb_mod_length, c);
360 g_free(one_file);
361 tmpl = tmpl->next;
362 }
363 g_list_free(mods);
364 }
365
366 /* Commandline support */
367 kcmdline = g_strdup_printf("%s %s", kernel_filename, kernel_cmdline);
368 stl_le_p(bootinfo + MBI_CMDLINE, mb_add_cmdline(&mbs, kcmdline));
369 stl_le_p(bootinfo + MBI_BOOTLOADER, mb_add_bootloader(&mbs,
370 bootloader_name));
371 stl_le_p(bootinfo + MBI_MODS_ADDR, mbs.mb_buf_phys + mbs.offset_mbinfo);
372 stl_le_p(bootinfo + MBI_MODS_COUNT, mbs.mb_mods_count); /* mods_count */
373
374 /* the kernel is where we want it to be now */
375 stl_le_p(bootinfo + MBI_FLAGS, MULTIBOOT_FLAGS_MEMORY
376 | MULTIBOOT_FLAGS_BOOT_DEVICE
377 | MULTIBOOT_FLAGS_CMDLINE
378 | MULTIBOOT_FLAGS_MODULES
379 | MULTIBOOT_FLAGS_MMAP
380 | MULTIBOOT_FLAGS_BOOTLOADER);
381 stl_le_p(bootinfo + MBI_BOOT_DEVICE, 0x8000ffff); /* XXX: use the -boot switch? */
382 stl_le_p(bootinfo + MBI_MMAP_ADDR, ADDR_E820_MAP);
383
384 mb_debug("multiboot: entry_addr = %#x", mh_entry_addr);
385 mb_debug(" mb_buf_phys = "HWADDR_FMT_plx, mbs.mb_buf_phys);
386 mb_debug(" mod_start = "HWADDR_FMT_plx,
387 mbs.mb_buf_phys + mbs.offset_mods);
388 mb_debug(" mb_mods_count = %d", mbs.mb_mods_count);
389
390 /* save bootinfo off the stack */
391 mb_bootinfo_data = g_memdup(bootinfo, sizeof(bootinfo));
392
393 /* Pass variables to option rom */
394 fw_cfg_add_i32(fw_cfg, FW_CFG_KERNEL_ENTRY, mh_entry_addr);
395 fw_cfg_add_i32(fw_cfg, FW_CFG_KERNEL_ADDR, mh_load_addr);
396 fw_cfg_add_i32(fw_cfg, FW_CFG_KERNEL_SIZE, mbs.mb_buf_size);
397 fw_cfg_add_bytes(fw_cfg, FW_CFG_KERNEL_DATA,
398 mbs.mb_buf, mbs.mb_buf_size);
399
400 fw_cfg_add_i32(fw_cfg, FW_CFG_INITRD_ADDR, ADDR_MBI);
401 fw_cfg_add_i32(fw_cfg, FW_CFG_INITRD_SIZE, sizeof(bootinfo));
402 fw_cfg_add_bytes(fw_cfg, FW_CFG_INITRD_DATA, mb_bootinfo_data,
403 sizeof(bootinfo));
404
405 if (multiboot_dma_enabled) {
406 option_rom[nb_option_roms].name = "multiboot_dma.bin";
407 } else {
408 option_rom[nb_option_roms].name = "multiboot.bin";
409 }
410 option_rom[nb_option_roms].bootindex = 0;
411 nb_option_roms++;
412
413 return 1; /* yes, we are multiboot */
414 }
415