Commit | Line | Data |
---|---|---|
c67e5382 HS |
1 | /* |
2 | * Many of the syscalls used in this file expect some of the arguments | |
3 | * to be __user pointers not __kernel pointers. To limit the sparse | |
4 | * noise, turn off sparse checking for this file. | |
5 | */ | |
6 | #ifdef __CHECKER__ | |
7 | #undef __CHECKER__ | |
8 | #warning "Sparse checking disabled for this file" | |
9 | #endif | |
1da177e4 LT |
10 | |
11 | #include <linux/kernel.h> | |
12 | #include <linux/fs.h> | |
13 | #include <linux/minix_fs.h> | |
14 | #include <linux/ext2_fs.h> | |
15 | #include <linux/romfs_fs.h> | |
16 | #include <linux/cramfs_fs.h> | |
17 | #include <linux/initrd.h> | |
18 | #include <linux/string.h> | |
5a0e3ad6 | 19 | #include <linux/slab.h> |
1da177e4 LT |
20 | |
21 | #include "do_mounts.h" | |
b8fed87d | 22 | #include "../fs/squashfs/squashfs_fs.h" |
1da177e4 | 23 | |
30d65dbf AK |
24 | #include <linux/decompress/generic.h> |
25 | ||
30d65dbf | 26 | |
1da177e4 LT |
27 | int __initdata rd_prompt = 1;/* 1 = prompt for RAM disk, 0 = don't prompt */ |
28 | ||
29 | static int __init prompt_ramdisk(char *str) | |
30 | { | |
31 | rd_prompt = simple_strtol(str,NULL,0) & 1; | |
32 | return 1; | |
33 | } | |
34 | __setup("prompt_ramdisk=", prompt_ramdisk); | |
35 | ||
36 | int __initdata rd_image_start; /* starting block # of image */ | |
37 | ||
38 | static int __init ramdisk_start_setup(char *str) | |
39 | { | |
40 | rd_image_start = simple_strtol(str,NULL,0); | |
41 | return 1; | |
42 | } | |
43 | __setup("ramdisk_start=", ramdisk_start_setup); | |
44 | ||
30d65dbf | 45 | static int __init crd_load(int in_fd, int out_fd, decompress_fn deco); |
1da177e4 LT |
46 | |
47 | /* | |
48 | * This routine tries to find a RAM disk image to load, and returns the | |
49 | * number of blocks to read for a non-compressed image, 0 if the image | |
50 | * is a compressed image, and -1 if an image with the right magic | |
51 | * numbers could not be found. | |
52 | * | |
53 | * We currently check for the following magic numbers: | |
b172fd88 PA |
54 | * minix |
55 | * ext2 | |
1da177e4 LT |
56 | * romfs |
57 | * cramfs | |
b8fed87d | 58 | * squashfs |
b172fd88 | 59 | * gzip |
1da177e4 | 60 | */ |
b172fd88 | 61 | static int __init |
30d65dbf | 62 | identify_ramdisk_image(int fd, int start_block, decompress_fn *decompressor) |
1da177e4 LT |
63 | { |
64 | const int size = 512; | |
65 | struct minix_super_block *minixsb; | |
1da177e4 LT |
66 | struct romfs_super_block *romfsb; |
67 | struct cramfs_super *cramfsb; | |
b8fed87d | 68 | struct squashfs_super_block *squashfsb; |
1da177e4 LT |
69 | int nblocks = -1; |
70 | unsigned char *buf; | |
889c92d2 | 71 | const char *compress_name; |
39429c5e | 72 | unsigned long n; |
1da177e4 LT |
73 | |
74 | buf = kmalloc(size, GFP_KERNEL); | |
c80544dc | 75 | if (!buf) |
ea611b26 | 76 | return -ENOMEM; |
1da177e4 LT |
77 | |
78 | minixsb = (struct minix_super_block *) buf; | |
1da177e4 LT |
79 | romfsb = (struct romfs_super_block *) buf; |
80 | cramfsb = (struct cramfs_super *) buf; | |
b8fed87d | 81 | squashfsb = (struct squashfs_super_block *) buf; |
1da177e4 LT |
82 | memset(buf, 0xe5, size); |
83 | ||
84 | /* | |
b172fd88 | 85 | * Read block 0 to test for compressed kernel |
1da177e4 LT |
86 | */ |
87 | sys_lseek(fd, start_block * BLOCK_SIZE, 0); | |
88 | sys_read(fd, buf, size); | |
89 | ||
889c92d2 | 90 | *decompressor = decompress_method(buf, size, &compress_name); |
23a22d57 | 91 | if (compress_name) { |
889c92d2 PA |
92 | printk(KERN_NOTICE "RAMDISK: %s image found at block %d\n", |
93 | compress_name, start_block); | |
23a22d57 | 94 | if (!*decompressor) |
73310a16 PA |
95 | printk(KERN_EMERG |
96 | "RAMDISK: %s decompressor not configured!\n", | |
23a22d57 | 97 | compress_name); |
889c92d2 PA |
98 | nblocks = 0; |
99 | goto done; | |
1da177e4 LT |
100 | } |
101 | ||
102 | /* romfs is at block zero too */ | |
103 | if (romfsb->word0 == ROMSB_WORD0 && | |
104 | romfsb->word1 == ROMSB_WORD1) { | |
105 | printk(KERN_NOTICE | |
106 | "RAMDISK: romfs filesystem found at block %d\n", | |
107 | start_block); | |
108 | nblocks = (ntohl(romfsb->size)+BLOCK_SIZE-1)>>BLOCK_SIZE_BITS; | |
109 | goto done; | |
110 | } | |
111 | ||
112 | if (cramfsb->magic == CRAMFS_MAGIC) { | |
113 | printk(KERN_NOTICE | |
114 | "RAMDISK: cramfs filesystem found at block %d\n", | |
115 | start_block); | |
116 | nblocks = (cramfsb->size + BLOCK_SIZE - 1) >> BLOCK_SIZE_BITS; | |
117 | goto done; | |
118 | } | |
119 | ||
b8fed87d PL |
120 | /* squashfs is at block zero too */ |
121 | if (le32_to_cpu(squashfsb->s_magic) == SQUASHFS_MAGIC) { | |
122 | printk(KERN_NOTICE | |
123 | "RAMDISK: squashfs filesystem found at block %d\n", | |
124 | start_block); | |
125 | nblocks = (le64_to_cpu(squashfsb->bytes_used) + BLOCK_SIZE - 1) | |
126 | >> BLOCK_SIZE_BITS; | |
127 | goto done; | |
128 | } | |
129 | ||
f919b923 NA |
130 | /* |
131 | * Read 512 bytes further to check if cramfs is padded | |
132 | */ | |
133 | sys_lseek(fd, start_block * BLOCK_SIZE + 0x200, 0); | |
134 | sys_read(fd, buf, size); | |
135 | ||
136 | if (cramfsb->magic == CRAMFS_MAGIC) { | |
137 | printk(KERN_NOTICE | |
138 | "RAMDISK: cramfs filesystem found at block %d\n", | |
139 | start_block); | |
140 | nblocks = (cramfsb->size + BLOCK_SIZE - 1) >> BLOCK_SIZE_BITS; | |
141 | goto done; | |
142 | } | |
143 | ||
1da177e4 LT |
144 | /* |
145 | * Read block 1 to test for minix and ext2 superblock | |
146 | */ | |
147 | sys_lseek(fd, (start_block+1) * BLOCK_SIZE, 0); | |
148 | sys_read(fd, buf, size); | |
149 | ||
150 | /* Try minix */ | |
151 | if (minixsb->s_magic == MINIX_SUPER_MAGIC || | |
152 | minixsb->s_magic == MINIX_SUPER_MAGIC2) { | |
153 | printk(KERN_NOTICE | |
154 | "RAMDISK: Minix filesystem found at block %d\n", | |
155 | start_block); | |
156 | nblocks = minixsb->s_nzones << minixsb->s_log_zone_size; | |
157 | goto done; | |
158 | } | |
159 | ||
160 | /* Try ext2 */ | |
39429c5e AV |
161 | n = ext2_image_size(buf); |
162 | if (n) { | |
1da177e4 LT |
163 | printk(KERN_NOTICE |
164 | "RAMDISK: ext2 filesystem found at block %d\n", | |
165 | start_block); | |
39429c5e | 166 | nblocks = n; |
1da177e4 LT |
167 | goto done; |
168 | } | |
169 | ||
170 | printk(KERN_NOTICE | |
171 | "RAMDISK: Couldn't find valid RAM disk image starting at %d.\n", | |
172 | start_block); | |
b172fd88 | 173 | |
1da177e4 LT |
174 | done: |
175 | sys_lseek(fd, start_block * BLOCK_SIZE, 0); | |
176 | kfree(buf); | |
177 | return nblocks; | |
178 | } | |
179 | ||
180 | int __init rd_load_image(char *from) | |
181 | { | |
182 | int res = 0; | |
183 | int in_fd, out_fd; | |
184 | unsigned long rd_blocks, devblocks; | |
185 | int nblocks, i, disk; | |
186 | char *buf = NULL; | |
187 | unsigned short rotate = 0; | |
30d65dbf | 188 | decompress_fn decompressor = NULL; |
bc58450b | 189 | #if !defined(CONFIG_S390) |
1da177e4 LT |
190 | char rotator[4] = { '|' , '/' , '-' , '\\' }; |
191 | #endif | |
192 | ||
c67e5382 | 193 | out_fd = sys_open("/dev/ram", O_RDWR, 0); |
1da177e4 LT |
194 | if (out_fd < 0) |
195 | goto out; | |
196 | ||
197 | in_fd = sys_open(from, O_RDONLY, 0); | |
198 | if (in_fd < 0) | |
199 | goto noclose_input; | |
200 | ||
30d65dbf | 201 | nblocks = identify_ramdisk_image(in_fd, rd_image_start, &decompressor); |
1da177e4 LT |
202 | if (nblocks < 0) |
203 | goto done; | |
204 | ||
205 | if (nblocks == 0) { | |
30d65dbf | 206 | if (crd_load(in_fd, out_fd, decompressor) == 0) |
1da177e4 | 207 | goto successful_load; |
1da177e4 LT |
208 | goto done; |
209 | } | |
210 | ||
211 | /* | |
212 | * NOTE NOTE: nblocks is not actually blocks but | |
213 | * the number of kibibytes of data to load into a ramdisk. | |
214 | * So any ramdisk block size that is a multiple of 1KiB should | |
215 | * work when the appropriate ramdisk_blocksize is specified | |
216 | * on the command line. | |
217 | * | |
218 | * The default ramdisk_blocksize is 1KiB and it is generally | |
219 | * silly to use anything else, so make sure to use 1KiB | |
220 | * blocksize while generating ext2fs ramdisk-images. | |
221 | */ | |
222 | if (sys_ioctl(out_fd, BLKGETSIZE, (unsigned long)&rd_blocks) < 0) | |
223 | rd_blocks = 0; | |
224 | else | |
225 | rd_blocks >>= 1; | |
226 | ||
227 | if (nblocks > rd_blocks) { | |
228 | printk("RAMDISK: image too big! (%dKiB/%ldKiB)\n", | |
229 | nblocks, rd_blocks); | |
230 | goto done; | |
231 | } | |
b172fd88 | 232 | |
1da177e4 LT |
233 | /* |
234 | * OK, time to copy in the data | |
235 | */ | |
236 | if (sys_ioctl(in_fd, BLKGETSIZE, (unsigned long)&devblocks) < 0) | |
237 | devblocks = 0; | |
238 | else | |
239 | devblocks >>= 1; | |
240 | ||
241 | if (strcmp(from, "/initrd.image") == 0) | |
242 | devblocks = nblocks; | |
243 | ||
244 | if (devblocks == 0) { | |
245 | printk(KERN_ERR "RAMDISK: could not determine device size\n"); | |
246 | goto done; | |
247 | } | |
248 | ||
249 | buf = kmalloc(BLOCK_SIZE, GFP_KERNEL); | |
d613c3e2 | 250 | if (!buf) { |
1da177e4 LT |
251 | printk(KERN_ERR "RAMDISK: could not allocate buffer\n"); |
252 | goto done; | |
253 | } | |
254 | ||
255 | printk(KERN_NOTICE "RAMDISK: Loading %dKiB [%ld disk%s] into ram disk... ", | |
256 | nblocks, ((nblocks-1)/devblocks)+1, nblocks>devblocks ? "s" : ""); | |
257 | for (i = 0, disk = 1; i < nblocks; i++) { | |
258 | if (i && (i % devblocks == 0)) { | |
259 | printk("done disk #%d.\n", disk++); | |
260 | rotate = 0; | |
261 | if (sys_close(in_fd)) { | |
262 | printk("Error closing the disk.\n"); | |
263 | goto noclose_input; | |
264 | } | |
265 | change_floppy("disk #%d", disk); | |
266 | in_fd = sys_open(from, O_RDONLY, 0); | |
267 | if (in_fd < 0) { | |
268 | printk("Error opening disk.\n"); | |
269 | goto noclose_input; | |
270 | } | |
271 | printk("Loading disk #%d... ", disk); | |
272 | } | |
273 | sys_read(in_fd, buf, BLOCK_SIZE); | |
274 | sys_write(out_fd, buf, BLOCK_SIZE); | |
bc58450b | 275 | #if !defined(CONFIG_S390) |
1da177e4 LT |
276 | if (!(i % 16)) { |
277 | printk("%c\b", rotator[rotate & 0x3]); | |
278 | rotate++; | |
279 | } | |
280 | #endif | |
281 | } | |
282 | printk("done.\n"); | |
283 | ||
284 | successful_load: | |
285 | res = 1; | |
286 | done: | |
287 | sys_close(in_fd); | |
288 | noclose_input: | |
289 | sys_close(out_fd); | |
290 | out: | |
291 | kfree(buf); | |
c67e5382 | 292 | sys_unlink("/dev/ram"); |
1da177e4 LT |
293 | return res; |
294 | } | |
295 | ||
296 | int __init rd_load_disk(int n) | |
297 | { | |
298 | if (rd_prompt) | |
299 | change_floppy("root floppy disk to be loaded into RAM disk"); | |
bdaf8529 GKH |
300 | create_dev("/dev/root", ROOT_DEV); |
301 | create_dev("/dev/ram", MKDEV(RAMDISK_MAJOR, n)); | |
1da177e4 LT |
302 | return rd_load_image("/dev/root"); |
303 | } | |
304 | ||
1da177e4 | 305 | static int exit_code; |
30d65dbf | 306 | static int decompress_error; |
1da177e4 LT |
307 | static int crd_infd, crd_outfd; |
308 | ||
30d65dbf | 309 | static int __init compr_fill(void *buf, unsigned int len) |
1da177e4 | 310 | { |
30d65dbf AK |
311 | int r = sys_read(crd_infd, buf, len); |
312 | if (r < 0) | |
313 | printk(KERN_ERR "RAMDISK: error while reading compressed data"); | |
314 | else if (r == 0) | |
315 | printk(KERN_ERR "RAMDISK: EOF while reading compressed data"); | |
316 | return r; | |
1da177e4 LT |
317 | } |
318 | ||
30d65dbf | 319 | static int __init compr_flush(void *window, unsigned int outcnt) |
1da177e4 | 320 | { |
30d65dbf AK |
321 | int written = sys_write(crd_outfd, window, outcnt); |
322 | if (written != outcnt) { | |
323 | if (decompress_error == 0) | |
324 | printk(KERN_ERR | |
325 | "RAMDISK: incomplete write (%d != %d)\n", | |
326 | written, outcnt); | |
327 | decompress_error = 1; | |
328 | return -1; | |
329 | } | |
330 | return outcnt; | |
1da177e4 LT |
331 | } |
332 | ||
333 | static void __init error(char *x) | |
334 | { | |
335 | printk(KERN_ERR "%s\n", x); | |
336 | exit_code = 1; | |
30d65dbf | 337 | decompress_error = 1; |
1da177e4 LT |
338 | } |
339 | ||
30d65dbf | 340 | static int __init crd_load(int in_fd, int out_fd, decompress_fn deco) |
1da177e4 LT |
341 | { |
342 | int result; | |
1da177e4 LT |
343 | crd_infd = in_fd; |
344 | crd_outfd = out_fd; | |
30d65dbf AK |
345 | result = deco(NULL, 0, compr_fill, compr_flush, NULL, NULL, error); |
346 | if (decompress_error) | |
1da177e4 | 347 | result = 1; |
1da177e4 LT |
348 | return result; |
349 | } |