aboutsummaryrefslogtreecommitdiffstats
path: root/arch/ppc64/boot/addRamDisk.c
diff options
context:
space:
mode:
Diffstat (limited to 'arch/ppc64/boot/addRamDisk.c')
-rw-r--r--arch/ppc64/boot/addRamDisk.c300
1 files changed, 300 insertions, 0 deletions
diff --git a/arch/ppc64/boot/addRamDisk.c b/arch/ppc64/boot/addRamDisk.c
new file mode 100644
index 00000000000..7f2c0947339
--- /dev/null
+++ b/arch/ppc64/boot/addRamDisk.c
@@ -0,0 +1,300 @@
1#include <stdio.h>
2#include <stdlib.h>
3#include <netinet/in.h>
4#include <unistd.h>
5#include <sys/types.h>
6#include <sys/stat.h>
7#include <string.h>
8
9#define ElfHeaderSize (64 * 1024)
10#define ElfPages (ElfHeaderSize / 4096)
11#define KERNELBASE (0xc000000000000000)
12
13void get4k(FILE *file, char *buf )
14{
15 unsigned j;
16 unsigned num = fread(buf, 1, 4096, file);
17 for ( j=num; j<4096; ++j )
18 buf[j] = 0;
19}
20
21void put4k(FILE *file, char *buf )
22{
23 fwrite(buf, 1, 4096, file);
24}
25
26void death(const char *msg, FILE *fdesc, const char *fname)
27{
28 fprintf(stderr, msg);
29 fclose(fdesc);
30 unlink(fname);
31 exit(1);
32}
33
34int main(int argc, char **argv)
35{
36 char inbuf[4096];
37 FILE *ramDisk = NULL;
38 FILE *sysmap = NULL;
39 FILE *inputVmlinux = NULL;
40 FILE *outputVmlinux = NULL;
41
42 unsigned i = 0;
43 unsigned long ramFileLen = 0;
44 unsigned long ramLen = 0;
45 unsigned long roundR = 0;
46
47 unsigned long sysmapFileLen = 0;
48 unsigned long sysmapLen = 0;
49 unsigned long sysmapPages = 0;
50 char* ptr_end = NULL;
51 unsigned long offset_end = 0;
52
53 unsigned long kernelLen = 0;
54 unsigned long actualKernelLen = 0;
55 unsigned long round = 0;
56 unsigned long roundedKernelLen = 0;
57 unsigned long ramStartOffs = 0;
58 unsigned long ramPages = 0;
59 unsigned long roundedKernelPages = 0;
60 unsigned long hvReleaseData = 0;
61 u_int32_t eyeCatcher = 0xc8a5d9c4;
62 unsigned long naca = 0;
63 unsigned long xRamDisk = 0;
64 unsigned long xRamDiskSize = 0;
65 long padPages = 0;
66
67
68 if (argc < 2) {
69 fprintf(stderr, "Name of RAM disk file missing.\n");
70 exit(1);
71 }
72
73 if (argc < 3) {
74 fprintf(stderr, "Name of System Map input file is missing.\n");
75 exit(1);
76 }
77
78 if (argc < 4) {
79 fprintf(stderr, "Name of vmlinux file missing.\n");
80 exit(1);
81 }
82
83 if (argc < 5) {
84 fprintf(stderr, "Name of vmlinux output file missing.\n");
85 exit(1);
86 }
87
88
89 ramDisk = fopen(argv[1], "r");
90 if ( ! ramDisk ) {
91 fprintf(stderr, "RAM disk file \"%s\" failed to open.\n", argv[1]);
92 exit(1);
93 }
94
95 sysmap = fopen(argv[2], "r");
96 if ( ! sysmap ) {
97 fprintf(stderr, "System Map file \"%s\" failed to open.\n", argv[2]);
98 exit(1);
99 }
100
101 inputVmlinux = fopen(argv[3], "r");
102 if ( ! inputVmlinux ) {
103 fprintf(stderr, "vmlinux file \"%s\" failed to open.\n", argv[3]);
104 exit(1);
105 }
106
107 outputVmlinux = fopen(argv[4], "w+");
108 if ( ! outputVmlinux ) {
109 fprintf(stderr, "output vmlinux file \"%s\" failed to open.\n", argv[4]);
110 exit(1);
111 }
112
113
114
115 /* Input Vmlinux file */
116 fseek(inputVmlinux, 0, SEEK_END);
117 kernelLen = ftell(inputVmlinux);
118 fseek(inputVmlinux, 0, SEEK_SET);
119 printf("kernel file size = %d\n", kernelLen);
120 if ( kernelLen == 0 ) {
121 fprintf(stderr, "You must have a linux kernel specified as argv[3]\n");
122 exit(1);
123 }
124
125 actualKernelLen = kernelLen - ElfHeaderSize;
126
127 printf("actual kernel length (minus ELF header) = %d\n", actualKernelLen);
128
129 round = actualKernelLen % 4096;
130 roundedKernelLen = actualKernelLen;
131 if ( round )
132 roundedKernelLen += (4096 - round);
133 printf("Vmlinux length rounded up to a 4k multiple = %ld/0x%lx \n", roundedKernelLen, roundedKernelLen);
134 roundedKernelPages = roundedKernelLen / 4096;
135 printf("Vmlinux pages to copy = %ld/0x%lx \n", roundedKernelPages, roundedKernelPages);
136
137
138
139 /* Input System Map file */
140 /* (needs to be processed simply to determine if we need to add pad pages due to the static variables not being included in the vmlinux) */
141 fseek(sysmap, 0, SEEK_END);
142 sysmapFileLen = ftell(sysmap);
143 fseek(sysmap, 0, SEEK_SET);
144 printf("%s file size = %ld/0x%lx \n", argv[2], sysmapFileLen, sysmapFileLen);
145
146 sysmapLen = sysmapFileLen;
147
148 roundR = 4096 - (sysmapLen % 4096);
149 if (roundR) {
150 printf("Rounding System Map file up to a multiple of 4096, adding %ld/0x%lx \n", roundR, roundR);
151 sysmapLen += roundR;
152 }
153 printf("Rounded System Map size is %ld/0x%lx \n", sysmapLen, sysmapLen);
154
155 /* Process the Sysmap file to determine where _end is */
156 sysmapPages = sysmapLen / 4096;
157 /* read the whole file line by line, expect that it doesn't fail */
158 while ( fgets(inbuf, 4096, sysmap) ) ;
159 /* search for _end in the last page of the system map */
160 ptr_end = strstr(inbuf, " _end");
161 if (!ptr_end) {
162 fprintf(stderr, "Unable to find _end in the sysmap file \n");
163 fprintf(stderr, "inbuf: \n");
164 fprintf(stderr, "%s \n", inbuf);
165 exit(1);
166 }
167 printf("Found _end in the last page of the sysmap - backing up 10 characters it looks like %s", ptr_end-10);
168 /* convert address of _end in system map to hex offset. */
169 offset_end = (unsigned int)strtol(ptr_end-10, NULL, 16);
170 /* calc how many pages we need to insert between the vmlinux and the start of the ram disk */
171 padPages = offset_end/4096 - roundedKernelPages;
172
173 /* Check and see if the vmlinux is already larger than _end in System.map */
174 if (padPages < 0) {
175 /* vmlinux is larger than _end - adjust the offset to the start of the embedded ram disk */
176 offset_end = roundedKernelLen;
177 printf("vmlinux is larger than _end indicates it needs to be - offset_end = %lx \n", offset_end);
178 padPages = 0;
179 printf("will insert %lx pages between the vmlinux and the start of the ram disk \n", padPages);
180 }
181 else {
182 /* _end is larger than vmlinux - use the offset to _end that we calculated from the system map */
183 printf("vmlinux is smaller than _end indicates is needed - offset_end = %lx \n", offset_end);
184 printf("will insert %lx pages between the vmlinux and the start of the ram disk \n", padPages);
185 }
186
187
188
189 /* Input Ram Disk file */
190 // Set the offset that the ram disk will be started at.
191 ramStartOffs = offset_end; /* determined from the input vmlinux file and the system map */
192 printf("Ram Disk will start at offset = 0x%lx \n", ramStartOffs);
193
194 fseek(ramDisk, 0, SEEK_END);
195 ramFileLen = ftell(ramDisk);
196 fseek(ramDisk, 0, SEEK_SET);
197 printf("%s file size = %ld/0x%lx \n", argv[1], ramFileLen, ramFileLen);
198
199 ramLen = ramFileLen;
200
201 roundR = 4096 - (ramLen % 4096);
202 if ( roundR ) {
203 printf("Rounding RAM disk file up to a multiple of 4096, adding %ld/0x%lx \n", roundR, roundR);
204 ramLen += roundR;
205 }
206
207 printf("Rounded RAM disk size is %ld/0x%lx \n", ramLen, ramLen);
208 ramPages = ramLen / 4096;
209 printf("RAM disk pages to copy = %ld/0x%lx\n", ramPages, ramPages);
210
211
212
213 // Copy 64K ELF header
214 for (i=0; i<(ElfPages); ++i) {
215 get4k( inputVmlinux, inbuf );
216 put4k( outputVmlinux, inbuf );
217 }
218
219 /* Copy the vmlinux (as full pages). */
220 fseek(inputVmlinux, ElfHeaderSize, SEEK_SET);
221 for ( i=0; i<roundedKernelPages; ++i ) {
222 get4k( inputVmlinux, inbuf );
223 put4k( outputVmlinux, inbuf );
224 }
225
226 /* Insert pad pages (if appropriate) that are needed between */
227 /* | the end of the vmlinux and the ram disk. */
228 for (i=0; i<padPages; ++i) {
229 memset(inbuf, 0, 4096);
230 put4k(outputVmlinux, inbuf);
231 }
232
233 /* Copy the ram disk (as full pages). */
234 for ( i=0; i<ramPages; ++i ) {
235 get4k( ramDisk, inbuf );
236 put4k( outputVmlinux, inbuf );
237 }
238
239 /* Close the input files */
240 fclose(ramDisk);
241 fclose(inputVmlinux);
242 /* And flush the written output file */
243 fflush(outputVmlinux);
244
245
246
247 /* Fixup the new vmlinux to contain the ram disk starting offset (xRamDisk) and the ram disk size (xRamDiskSize) */
248 /* fseek to the hvReleaseData pointer */
249 fseek(outputVmlinux, ElfHeaderSize + 0x24, SEEK_SET);
250 if (fread(&hvReleaseData, 4, 1, outputVmlinux) != 1) {
251 death("Could not read hvReleaseData pointer\n", outputVmlinux, argv[4]);
252 }
253 hvReleaseData = ntohl(hvReleaseData); /* Convert to native int */
254 printf("hvReleaseData is at %08x\n", hvReleaseData);
255
256 /* fseek to the hvReleaseData */
257 fseek(outputVmlinux, ElfHeaderSize + hvReleaseData, SEEK_SET);
258 if (fread(inbuf, 0x40, 1, outputVmlinux) != 1) {
259 death("Could not read hvReleaseData\n", outputVmlinux, argv[4]);
260 }
261 /* Check hvReleaseData sanity */
262 if (memcmp(inbuf, &eyeCatcher, 4) != 0) {
263 death("hvReleaseData is invalid\n", outputVmlinux, argv[4]);
264 }
265 /* Get the naca pointer */
266 naca = ntohl(*((u_int32_t*) &inbuf[0x0C])) - KERNELBASE;
267 printf("Naca is at offset 0x%lx \n", naca);
268
269 /* fseek to the naca */
270 fseek(outputVmlinux, ElfHeaderSize + naca, SEEK_SET);
271 if (fread(inbuf, 0x18, 1, outputVmlinux) != 1) {
272 death("Could not read naca\n", outputVmlinux, argv[4]);
273 }
274 xRamDisk = ntohl(*((u_int32_t *) &inbuf[0x0c]));
275 xRamDiskSize = ntohl(*((u_int32_t *) &inbuf[0x14]));
276 /* Make sure a RAM disk isn't already present */
277 if ((xRamDisk != 0) || (xRamDiskSize != 0)) {
278 death("RAM disk is already attached to this kernel\n", outputVmlinux, argv[4]);
279 }
280 /* Fill in the values */
281 *((u_int32_t *) &inbuf[0x0c]) = htonl(ramStartOffs);
282 *((u_int32_t *) &inbuf[0x14]) = htonl(ramPages);
283
284 /* Write out the new naca */
285 fflush(outputVmlinux);
286 fseek(outputVmlinux, ElfHeaderSize + naca, SEEK_SET);
287 if (fwrite(inbuf, 0x18, 1, outputVmlinux) != 1) {
288 death("Could not write naca\n", outputVmlinux, argv[4]);
289 }
290 printf("Ram Disk of 0x%lx pages is attached to the kernel at offset 0x%08x\n",
291 ramPages, ramStartOffs);
292
293 /* Done */
294 fclose(outputVmlinux);
295 /* Set permission to executable */
296 chmod(argv[4], S_IRUSR|S_IWUSR|S_IXUSR|S_IRGRP|S_IXGRP|S_IROTH|S_IXOTH);
297
298 return 0;
299}
300
generated by cgit v1.2.2 (git 2.25.0) at 2024-12-21 12:44:11 -0500