Commit | Line | Data |
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1da177e4 LT |
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 <linux/cramfs_fs.h> | |
8 | #include <linux/initrd.h> | |
9 | #include <linux/string.h> | |
10 | ||
11 | #include "do_mounts.h" | |
12 | ||
30d65dbf AK |
13 | #include <linux/decompress/generic.h> |
14 | ||
15 | #include <linux/decompress/bunzip2.h> | |
16 | #include <linux/decompress/unlzma.h> | |
17 | #include <linux/decompress/inflate.h> | |
18 | ||
1da177e4 LT |
19 | int __initdata rd_prompt = 1;/* 1 = prompt for RAM disk, 0 = don't prompt */ |
20 | ||
21 | static int __init prompt_ramdisk(char *str) | |
22 | { | |
23 | rd_prompt = simple_strtol(str,NULL,0) & 1; | |
24 | return 1; | |
25 | } | |
26 | __setup("prompt_ramdisk=", prompt_ramdisk); | |
27 | ||
28 | int __initdata rd_image_start; /* starting block # of image */ | |
29 | ||
30 | static int __init ramdisk_start_setup(char *str) | |
31 | { | |
32 | rd_image_start = simple_strtol(str,NULL,0); | |
33 | return 1; | |
34 | } | |
35 | __setup("ramdisk_start=", ramdisk_start_setup); | |
36 | ||
30d65dbf | 37 | static int __init crd_load(int in_fd, int out_fd, decompress_fn deco); |
1da177e4 LT |
38 | |
39 | /* | |
40 | * This routine tries to find a RAM disk image to load, and returns the | |
41 | * number of blocks to read for a non-compressed image, 0 if the image | |
42 | * is a compressed image, and -1 if an image with the right magic | |
43 | * numbers could not be found. | |
44 | * | |
45 | * We currently check for the following magic numbers: | |
b172fd88 PA |
46 | * minix |
47 | * ext2 | |
1da177e4 LT |
48 | * romfs |
49 | * cramfs | |
b172fd88 | 50 | * gzip |
1da177e4 | 51 | */ |
b172fd88 PA |
52 | static const struct compress_format { |
53 | unsigned char magic[2]; | |
54 | const char *name; | |
55 | decompress_fn decompressor; | |
56 | } compressed_formats[] = { | |
57 | #ifdef CONFIG_RD_GZIP | |
58 | { {037, 0213}, "gzip", gunzip }, | |
59 | { {037, 0236}, "gzip", gunzip }, | |
60 | #endif | |
61 | #ifdef CONFIG_RD_BZIP2 | |
62 | { {0x42, 0x5a}, "bzip2", bunzip2 }, | |
63 | #endif | |
64 | #ifdef CONFIG_RD_LZMA | |
65 | { {0x5d, 0x00}, "lzma", unlzma }, | |
66 | #endif | |
67 | { {0, 0}, NULL, NULL } | |
68 | }; | |
69 | ||
70 | static int __init | |
30d65dbf | 71 | identify_ramdisk_image(int fd, int start_block, decompress_fn *decompressor) |
1da177e4 LT |
72 | { |
73 | const int size = 512; | |
74 | struct minix_super_block *minixsb; | |
75 | struct ext2_super_block *ext2sb; | |
76 | struct romfs_super_block *romfsb; | |
77 | struct cramfs_super *cramfsb; | |
78 | int nblocks = -1; | |
79 | unsigned char *buf; | |
b172fd88 | 80 | const struct compress_format *cf; |
1da177e4 LT |
81 | |
82 | buf = kmalloc(size, GFP_KERNEL); | |
c80544dc | 83 | if (!buf) |
1da177e4 LT |
84 | return -1; |
85 | ||
86 | minixsb = (struct minix_super_block *) buf; | |
87 | ext2sb = (struct ext2_super_block *) buf; | |
88 | romfsb = (struct romfs_super_block *) buf; | |
89 | cramfsb = (struct cramfs_super *) buf; | |
90 | memset(buf, 0xe5, size); | |
91 | ||
92 | /* | |
b172fd88 | 93 | * Read block 0 to test for compressed kernel |
1da177e4 LT |
94 | */ |
95 | sys_lseek(fd, start_block * BLOCK_SIZE, 0); | |
96 | sys_read(fd, buf, size); | |
97 | ||
b172fd88 PA |
98 | for (cf = compressed_formats; cf->decompressor; cf++) { |
99 | if (buf[0] == cf->magic[0] && buf[1] == cf->magic[1]) { | |
100 | printk(KERN_NOTICE | |
101 | "RAMDISK: %s image found at block %d\n", | |
102 | cf->name, start_block); | |
103 | *decompressor = cf->decompressor; | |
104 | nblocks = 0; | |
105 | goto done; | |
106 | } | |
1da177e4 LT |
107 | } |
108 | ||
109 | /* romfs is at block zero too */ | |
110 | if (romfsb->word0 == ROMSB_WORD0 && | |
111 | romfsb->word1 == ROMSB_WORD1) { | |
112 | printk(KERN_NOTICE | |
113 | "RAMDISK: romfs filesystem found at block %d\n", | |
114 | start_block); | |
115 | nblocks = (ntohl(romfsb->size)+BLOCK_SIZE-1)>>BLOCK_SIZE_BITS; | |
116 | goto done; | |
117 | } | |
118 | ||
119 | if (cramfsb->magic == CRAMFS_MAGIC) { | |
120 | printk(KERN_NOTICE | |
121 | "RAMDISK: cramfs filesystem found at block %d\n", | |
122 | start_block); | |
123 | nblocks = (cramfsb->size + BLOCK_SIZE - 1) >> BLOCK_SIZE_BITS; | |
124 | goto done; | |
125 | } | |
126 | ||
127 | /* | |
128 | * Read block 1 to test for minix and ext2 superblock | |
129 | */ | |
130 | sys_lseek(fd, (start_block+1) * BLOCK_SIZE, 0); | |
131 | sys_read(fd, buf, size); | |
132 | ||
133 | /* Try minix */ | |
134 | if (minixsb->s_magic == MINIX_SUPER_MAGIC || | |
135 | minixsb->s_magic == MINIX_SUPER_MAGIC2) { | |
136 | printk(KERN_NOTICE | |
137 | "RAMDISK: Minix filesystem found at block %d\n", | |
138 | start_block); | |
139 | nblocks = minixsb->s_nzones << minixsb->s_log_zone_size; | |
140 | goto done; | |
141 | } | |
142 | ||
143 | /* Try ext2 */ | |
144 | if (ext2sb->s_magic == cpu_to_le16(EXT2_SUPER_MAGIC)) { | |
145 | printk(KERN_NOTICE | |
146 | "RAMDISK: ext2 filesystem found at block %d\n", | |
147 | start_block); | |
148 | nblocks = le32_to_cpu(ext2sb->s_blocks_count) << | |
149 | le32_to_cpu(ext2sb->s_log_block_size); | |
150 | goto done; | |
151 | } | |
152 | ||
153 | printk(KERN_NOTICE | |
154 | "RAMDISK: Couldn't find valid RAM disk image starting at %d.\n", | |
155 | start_block); | |
b172fd88 | 156 | |
1da177e4 LT |
157 | done: |
158 | sys_lseek(fd, start_block * BLOCK_SIZE, 0); | |
159 | kfree(buf); | |
160 | return nblocks; | |
161 | } | |
162 | ||
163 | int __init rd_load_image(char *from) | |
164 | { | |
165 | int res = 0; | |
166 | int in_fd, out_fd; | |
167 | unsigned long rd_blocks, devblocks; | |
168 | int nblocks, i, disk; | |
169 | char *buf = NULL; | |
170 | unsigned short rotate = 0; | |
30d65dbf | 171 | decompress_fn decompressor = NULL; |
347a8dc3 | 172 | #if !defined(CONFIG_S390) && !defined(CONFIG_PPC_ISERIES) |
1da177e4 LT |
173 | char rotator[4] = { '|' , '/' , '-' , '\\' }; |
174 | #endif | |
175 | ||
176 | out_fd = sys_open("/dev/ram", O_RDWR, 0); | |
177 | if (out_fd < 0) | |
178 | goto out; | |
179 | ||
180 | in_fd = sys_open(from, O_RDONLY, 0); | |
181 | if (in_fd < 0) | |
182 | goto noclose_input; | |
183 | ||
30d65dbf | 184 | nblocks = identify_ramdisk_image(in_fd, rd_image_start, &decompressor); |
1da177e4 LT |
185 | if (nblocks < 0) |
186 | goto done; | |
187 | ||
188 | if (nblocks == 0) { | |
30d65dbf | 189 | if (crd_load(in_fd, out_fd, decompressor) == 0) |
1da177e4 | 190 | goto successful_load; |
1da177e4 LT |
191 | goto done; |
192 | } | |
193 | ||
194 | /* | |
195 | * NOTE NOTE: nblocks is not actually blocks but | |
196 | * the number of kibibytes of data to load into a ramdisk. | |
197 | * So any ramdisk block size that is a multiple of 1KiB should | |
198 | * work when the appropriate ramdisk_blocksize is specified | |
199 | * on the command line. | |
200 | * | |
201 | * The default ramdisk_blocksize is 1KiB and it is generally | |
202 | * silly to use anything else, so make sure to use 1KiB | |
203 | * blocksize while generating ext2fs ramdisk-images. | |
204 | */ | |
205 | if (sys_ioctl(out_fd, BLKGETSIZE, (unsigned long)&rd_blocks) < 0) | |
206 | rd_blocks = 0; | |
207 | else | |
208 | rd_blocks >>= 1; | |
209 | ||
210 | if (nblocks > rd_blocks) { | |
211 | printk("RAMDISK: image too big! (%dKiB/%ldKiB)\n", | |
212 | nblocks, rd_blocks); | |
213 | goto done; | |
214 | } | |
b172fd88 | 215 | |
1da177e4 LT |
216 | /* |
217 | * OK, time to copy in the data | |
218 | */ | |
219 | if (sys_ioctl(in_fd, BLKGETSIZE, (unsigned long)&devblocks) < 0) | |
220 | devblocks = 0; | |
221 | else | |
222 | devblocks >>= 1; | |
223 | ||
224 | if (strcmp(from, "/initrd.image") == 0) | |
225 | devblocks = nblocks; | |
226 | ||
227 | if (devblocks == 0) { | |
228 | printk(KERN_ERR "RAMDISK: could not determine device size\n"); | |
229 | goto done; | |
230 | } | |
231 | ||
232 | buf = kmalloc(BLOCK_SIZE, GFP_KERNEL); | |
d613c3e2 | 233 | if (!buf) { |
1da177e4 LT |
234 | printk(KERN_ERR "RAMDISK: could not allocate buffer\n"); |
235 | goto done; | |
236 | } | |
237 | ||
238 | printk(KERN_NOTICE "RAMDISK: Loading %dKiB [%ld disk%s] into ram disk... ", | |
239 | nblocks, ((nblocks-1)/devblocks)+1, nblocks>devblocks ? "s" : ""); | |
240 | for (i = 0, disk = 1; i < nblocks; i++) { | |
241 | if (i && (i % devblocks == 0)) { | |
242 | printk("done disk #%d.\n", disk++); | |
243 | rotate = 0; | |
244 | if (sys_close(in_fd)) { | |
245 | printk("Error closing the disk.\n"); | |
246 | goto noclose_input; | |
247 | } | |
248 | change_floppy("disk #%d", disk); | |
249 | in_fd = sys_open(from, O_RDONLY, 0); | |
250 | if (in_fd < 0) { | |
251 | printk("Error opening disk.\n"); | |
252 | goto noclose_input; | |
253 | } | |
254 | printk("Loading disk #%d... ", disk); | |
255 | } | |
256 | sys_read(in_fd, buf, BLOCK_SIZE); | |
257 | sys_write(out_fd, buf, BLOCK_SIZE); | |
347a8dc3 | 258 | #if !defined(CONFIG_S390) && !defined(CONFIG_PPC_ISERIES) |
1da177e4 LT |
259 | if (!(i % 16)) { |
260 | printk("%c\b", rotator[rotate & 0x3]); | |
261 | rotate++; | |
262 | } | |
263 | #endif | |
264 | } | |
265 | printk("done.\n"); | |
266 | ||
267 | successful_load: | |
268 | res = 1; | |
269 | done: | |
270 | sys_close(in_fd); | |
271 | noclose_input: | |
272 | sys_close(out_fd); | |
273 | out: | |
274 | kfree(buf); | |
275 | sys_unlink("/dev/ram"); | |
276 | return res; | |
277 | } | |
278 | ||
279 | int __init rd_load_disk(int n) | |
280 | { | |
281 | if (rd_prompt) | |
282 | change_floppy("root floppy disk to be loaded into RAM disk"); | |
bdaf8529 GKH |
283 | create_dev("/dev/root", ROOT_DEV); |
284 | create_dev("/dev/ram", MKDEV(RAMDISK_MAJOR, n)); | |
1da177e4 LT |
285 | return rd_load_image("/dev/root"); |
286 | } | |
287 | ||
1da177e4 | 288 | static int exit_code; |
30d65dbf | 289 | static int decompress_error; |
1da177e4 LT |
290 | static int crd_infd, crd_outfd; |
291 | ||
30d65dbf | 292 | static int __init compr_fill(void *buf, unsigned int len) |
1da177e4 | 293 | { |
30d65dbf AK |
294 | int r = sys_read(crd_infd, buf, len); |
295 | if (r < 0) | |
296 | printk(KERN_ERR "RAMDISK: error while reading compressed data"); | |
297 | else if (r == 0) | |
298 | printk(KERN_ERR "RAMDISK: EOF while reading compressed data"); | |
299 | return r; | |
1da177e4 LT |
300 | } |
301 | ||
30d65dbf | 302 | static int __init compr_flush(void *window, unsigned int outcnt) |
1da177e4 | 303 | { |
30d65dbf AK |
304 | int written = sys_write(crd_outfd, window, outcnt); |
305 | if (written != outcnt) { | |
306 | if (decompress_error == 0) | |
307 | printk(KERN_ERR | |
308 | "RAMDISK: incomplete write (%d != %d)\n", | |
309 | written, outcnt); | |
310 | decompress_error = 1; | |
311 | return -1; | |
312 | } | |
313 | return outcnt; | |
1da177e4 LT |
314 | } |
315 | ||
316 | static void __init error(char *x) | |
317 | { | |
318 | printk(KERN_ERR "%s\n", x); | |
319 | exit_code = 1; | |
30d65dbf | 320 | decompress_error = 1; |
1da177e4 LT |
321 | } |
322 | ||
30d65dbf | 323 | static int __init crd_load(int in_fd, int out_fd, decompress_fn deco) |
1da177e4 LT |
324 | { |
325 | int result; | |
1da177e4 LT |
326 | crd_infd = in_fd; |
327 | crd_outfd = out_fd; | |
30d65dbf AK |
328 | result = deco(NULL, 0, compr_fill, compr_flush, NULL, NULL, error); |
329 | if (decompress_error) | |
1da177e4 | 330 | result = 1; |
1da177e4 LT |
331 | return result; |
332 | } |