1
2#include <linux/kernel.h>
3#include <linux/fs.h>
4#include <linux/minix_fs.h>
5#include <linux/ext2_fs.h>
6#include <linux/romfs_fs.h>
7#include <uapi/linux/cramfs_fs.h>
8#include <linux/initrd.h>
9#include <linux/string.h>
10#include <linux/slab.h>
11
12#include "do_mounts.h"
13#include "../fs/squashfs/squashfs_fs.h"
14
15#include <linux/decompress/generic.h>
16
17static struct file *in_file, *out_file;
18static loff_t in_pos, out_pos;
19
20static int __init prompt_ramdisk(char *str)
21{
22 pr_warn("ignoring the deprecated prompt_ramdisk= option\n");
23 return 1;
24}
25__setup("prompt_ramdisk=", prompt_ramdisk);
26
27int __initdata rd_image_start;
28
29static int __init ramdisk_start_setup(char *str)
30{
31 rd_image_start = simple_strtol(str,NULL,0);
32 return 1;
33}
34__setup("ramdisk_start=", ramdisk_start_setup);
35
36static int __init crd_load(decompress_fn deco);
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57static int __init
58identify_ramdisk_image(struct file *file, loff_t pos,
59 decompress_fn *decompressor)
60{
61 const int size = 512;
62 struct minix_super_block *minixsb;
63 struct romfs_super_block *romfsb;
64 struct cramfs_super *cramfsb;
65 struct squashfs_super_block *squashfsb;
66 int nblocks = -1;
67 unsigned char *buf;
68 const char *compress_name;
69 unsigned long n;
70 int start_block = rd_image_start;
71
72 buf = kmalloc(size, GFP_KERNEL);
73 if (!buf)
74 return -ENOMEM;
75
76 minixsb = (struct minix_super_block *) buf;
77 romfsb = (struct romfs_super_block *) buf;
78 cramfsb = (struct cramfs_super *) buf;
79 squashfsb = (struct squashfs_super_block *) buf;
80 memset(buf, 0xe5, size);
81
82
83
84
85 pos = start_block * BLOCK_SIZE;
86 kernel_read(file, buf, size, &pos);
87
88 *decompressor = decompress_method(buf, size, &compress_name);
89 if (compress_name) {
90 printk(KERN_NOTICE "RAMDISK: %s image found at block %d\n",
91 compress_name, start_block);
92 if (!*decompressor)
93 printk(KERN_EMERG
94 "RAMDISK: %s decompressor not configured!\n",
95 compress_name);
96 nblocks = 0;
97 goto done;
98 }
99
100
101 if (romfsb->word0 == ROMSB_WORD0 &&
102 romfsb->word1 == ROMSB_WORD1) {
103 printk(KERN_NOTICE
104 "RAMDISK: romfs filesystem found at block %d\n",
105 start_block);
106 nblocks = (ntohl(romfsb->size)+BLOCK_SIZE-1)>>BLOCK_SIZE_BITS;
107 goto done;
108 }
109
110 if (cramfsb->magic == CRAMFS_MAGIC) {
111 printk(KERN_NOTICE
112 "RAMDISK: cramfs filesystem found at block %d\n",
113 start_block);
114 nblocks = (cramfsb->size + BLOCK_SIZE - 1) >> BLOCK_SIZE_BITS;
115 goto done;
116 }
117
118
119 if (le32_to_cpu(squashfsb->s_magic) == SQUASHFS_MAGIC) {
120 printk(KERN_NOTICE
121 "RAMDISK: squashfs filesystem found at block %d\n",
122 start_block);
123 nblocks = (le64_to_cpu(squashfsb->bytes_used) + BLOCK_SIZE - 1)
124 >> BLOCK_SIZE_BITS;
125 goto done;
126 }
127
128
129
130
131 pos = start_block * BLOCK_SIZE + 0x200;
132 kernel_read(file, buf, size, &pos);
133
134 if (cramfsb->magic == CRAMFS_MAGIC) {
135 printk(KERN_NOTICE
136 "RAMDISK: cramfs filesystem found at block %d\n",
137 start_block);
138 nblocks = (cramfsb->size + BLOCK_SIZE - 1) >> BLOCK_SIZE_BITS;
139 goto done;
140 }
141
142
143
144
145 pos = (start_block + 1) * BLOCK_SIZE;
146 kernel_read(file, buf, size, &pos);
147
148
149 if (minixsb->s_magic == MINIX_SUPER_MAGIC ||
150 minixsb->s_magic == MINIX_SUPER_MAGIC2) {
151 printk(KERN_NOTICE
152 "RAMDISK: Minix filesystem found at block %d\n",
153 start_block);
154 nblocks = minixsb->s_nzones << minixsb->s_log_zone_size;
155 goto done;
156 }
157
158
159 n = ext2_image_size(buf);
160 if (n) {
161 printk(KERN_NOTICE
162 "RAMDISK: ext2 filesystem found at block %d\n",
163 start_block);
164 nblocks = n;
165 goto done;
166 }
167
168 printk(KERN_NOTICE
169 "RAMDISK: Couldn't find valid RAM disk image starting at %d.\n",
170 start_block);
171
172done:
173 kfree(buf);
174 return nblocks;
175}
176
177static unsigned long nr_blocks(struct file *file)
178{
179 struct inode *inode = file->f_mapping->host;
180
181 if (!S_ISBLK(inode->i_mode))
182 return 0;
183 return i_size_read(inode) >> 10;
184}
185
186int __init rd_load_image(char *from)
187{
188 int res = 0;
189 unsigned long rd_blocks, devblocks;
190 int nblocks, i;
191 char *buf = NULL;
192 unsigned short rotate = 0;
193 decompress_fn decompressor = NULL;
194#if !defined(CONFIG_S390)
195 char rotator[4] = { '|' , '/' , '-' , '\\' };
196#endif
197
198 out_file = filp_open("/dev/ram", O_RDWR, 0);
199 if (IS_ERR(out_file))
200 goto out;
201
202 in_file = filp_open(from, O_RDONLY, 0);
203 if (IS_ERR(in_file))
204 goto noclose_input;
205
206 in_pos = rd_image_start * BLOCK_SIZE;
207 nblocks = identify_ramdisk_image(in_file, in_pos, &decompressor);
208 if (nblocks < 0)
209 goto done;
210
211 if (nblocks == 0) {
212 if (crd_load(decompressor) == 0)
213 goto successful_load;
214 goto done;
215 }
216
217
218
219
220
221 rd_blocks = nr_blocks(out_file);
222 if (nblocks > rd_blocks) {
223 printk("RAMDISK: image too big! (%dKiB/%ldKiB)\n",
224 nblocks, rd_blocks);
225 goto done;
226 }
227
228
229
230
231 if (strcmp(from, "/initrd.image") == 0)
232 devblocks = nblocks;
233 else
234 devblocks = nr_blocks(in_file);
235
236 if (devblocks == 0) {
237 printk(KERN_ERR "RAMDISK: could not determine device size\n");
238 goto done;
239 }
240
241 buf = kmalloc(BLOCK_SIZE, GFP_KERNEL);
242 if (!buf) {
243 printk(KERN_ERR "RAMDISK: could not allocate buffer\n");
244 goto done;
245 }
246
247 printk(KERN_NOTICE "RAMDISK: Loading %dKiB [%ld disk%s] into ram disk... ",
248 nblocks, ((nblocks-1)/devblocks)+1, nblocks>devblocks ? "s" : "");
249 for (i = 0; i < nblocks; i++) {
250 if (i && (i % devblocks == 0)) {
251 pr_cont("done disk #1.\n");
252 rotate = 0;
253 fput(in_file);
254 break;
255 }
256 kernel_read(in_file, buf, BLOCK_SIZE, &in_pos);
257 kernel_write(out_file, buf, BLOCK_SIZE, &out_pos);
258#if !defined(CONFIG_S390)
259 if (!(i % 16)) {
260 pr_cont("%c\b", rotator[rotate & 0x3]);
261 rotate++;
262 }
263#endif
264 }
265 pr_cont("done.\n");
266
267successful_load:
268 res = 1;
269done:
270 fput(in_file);
271noclose_input:
272 fput(out_file);
273out:
274 kfree(buf);
275 init_unlink("/dev/ram");
276 return res;
277}
278
279int __init rd_load_disk(int n)
280{
281 create_dev("/dev/root", ROOT_DEV);
282 create_dev("/dev/ram", MKDEV(RAMDISK_MAJOR, n));
283 return rd_load_image("/dev/root");
284}
285
286static int exit_code;
287static int decompress_error;
288
289static long __init compr_fill(void *buf, unsigned long len)
290{
291 long r = kernel_read(in_file, buf, len, &in_pos);
292 if (r < 0)
293 printk(KERN_ERR "RAMDISK: error while reading compressed data");
294 else if (r == 0)
295 printk(KERN_ERR "RAMDISK: EOF while reading compressed data");
296 return r;
297}
298
299static long __init compr_flush(void *window, unsigned long outcnt)
300{
301 long written = kernel_write(out_file, window, outcnt, &out_pos);
302 if (written != outcnt) {
303 if (decompress_error == 0)
304 printk(KERN_ERR
305 "RAMDISK: incomplete write (%ld != %ld)\n",
306 written, outcnt);
307 decompress_error = 1;
308 return -1;
309 }
310 return outcnt;
311}
312
313static void __init error(char *x)
314{
315 printk(KERN_ERR "%s\n", x);
316 exit_code = 1;
317 decompress_error = 1;
318}
319
320static int __init crd_load(decompress_fn deco)
321{
322 int result;
323
324 if (!deco) {
325 pr_emerg("Invalid ramdisk decompression routine. "
326 "Select appropriate config option.\n");
327 panic("Could not decompress initial ramdisk image.");
328 }
329
330 result = deco(NULL, 0, compr_fill, compr_flush, NULL, NULL, error);
331 if (decompress_error)
332 result = 1;
333 return result;
334}
335
