blob: dd4104c9aa12c6a517ff7066d52ab6057d26e586
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 |
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 <uapi/linux/cramfs_fs.h> |
17 | #include <linux/initrd.h> |
18 | #include <linux/string.h> |
19 | #include <linux/slab.h> |
20 | |
21 | #include "do_mounts.h" |
22 | #include "../fs/squashfs/squashfs_fs.h" |
23 | |
24 | #include <linux/decompress/generic.h> |
25 | |
26 | |
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 | |
45 | static int __init crd_load(int in_fd, int out_fd, decompress_fn deco); |
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: |
54 | * minix |
55 | * ext2 |
56 | * romfs |
57 | * cramfs |
58 | * squashfs |
59 | * gzip |
60 | * bzip2 |
61 | * lzma |
62 | * xz |
63 | * lzo |
64 | * lz4 |
65 | */ |
66 | static int __init |
67 | identify_ramdisk_image(int fd, int start_block, decompress_fn *decompressor) |
68 | { |
69 | const int size = 512; |
70 | struct minix_super_block *minixsb; |
71 | struct romfs_super_block *romfsb; |
72 | struct cramfs_super *cramfsb; |
73 | struct squashfs_super_block *squashfsb; |
74 | int nblocks = -1; |
75 | unsigned char *buf; |
76 | const char *compress_name; |
77 | unsigned long n; |
78 | |
79 | buf = kmalloc(size, GFP_KERNEL); |
80 | if (!buf) |
81 | return -ENOMEM; |
82 | |
83 | minixsb = (struct minix_super_block *) buf; |
84 | romfsb = (struct romfs_super_block *) buf; |
85 | cramfsb = (struct cramfs_super *) buf; |
86 | squashfsb = (struct squashfs_super_block *) buf; |
87 | memset(buf, 0xe5, size); |
88 | |
89 | /* |
90 | * Read block 0 to test for compressed kernel |
91 | */ |
92 | sys_lseek(fd, start_block * BLOCK_SIZE, 0); |
93 | sys_read(fd, buf, size); |
94 | |
95 | *decompressor = decompress_method(buf, size, &compress_name); |
96 | if (compress_name) { |
97 | printk(KERN_NOTICE "RAMDISK: %s image found at block %d\n", |
98 | compress_name, start_block); |
99 | if (!*decompressor) |
100 | printk(KERN_EMERG |
101 | "RAMDISK: %s decompressor not configured!\n", |
102 | compress_name); |
103 | nblocks = 0; |
104 | goto done; |
105 | } |
106 | |
107 | /* romfs is at block zero too */ |
108 | if (romfsb->word0 == ROMSB_WORD0 && |
109 | romfsb->word1 == ROMSB_WORD1) { |
110 | printk(KERN_NOTICE |
111 | "RAMDISK: romfs filesystem found at block %d\n", |
112 | start_block); |
113 | nblocks = (ntohl(romfsb->size)+BLOCK_SIZE-1)>>BLOCK_SIZE_BITS; |
114 | goto done; |
115 | } |
116 | |
117 | if (cramfsb->magic == CRAMFS_MAGIC) { |
118 | printk(KERN_NOTICE |
119 | "RAMDISK: cramfs filesystem found at block %d\n", |
120 | start_block); |
121 | nblocks = (cramfsb->size + BLOCK_SIZE - 1) >> BLOCK_SIZE_BITS; |
122 | goto done; |
123 | } |
124 | |
125 | /* squashfs is at block zero too */ |
126 | if (le32_to_cpu(squashfsb->s_magic) == SQUASHFS_MAGIC) { |
127 | printk(KERN_NOTICE |
128 | "RAMDISK: squashfs filesystem found at block %d\n", |
129 | start_block); |
130 | nblocks = (le64_to_cpu(squashfsb->bytes_used) + BLOCK_SIZE - 1) |
131 | >> BLOCK_SIZE_BITS; |
132 | goto done; |
133 | } |
134 | |
135 | /* |
136 | * Read 512 bytes further to check if cramfs is padded |
137 | */ |
138 | sys_lseek(fd, start_block * BLOCK_SIZE + 0x200, 0); |
139 | sys_read(fd, buf, size); |
140 | |
141 | if (cramfsb->magic == CRAMFS_MAGIC) { |
142 | printk(KERN_NOTICE |
143 | "RAMDISK: cramfs filesystem found at block %d\n", |
144 | start_block); |
145 | nblocks = (cramfsb->size + BLOCK_SIZE - 1) >> BLOCK_SIZE_BITS; |
146 | goto done; |
147 | } |
148 | |
149 | /* |
150 | * Read block 1 to test for minix and ext2 superblock |
151 | */ |
152 | sys_lseek(fd, (start_block+1) * BLOCK_SIZE, 0); |
153 | sys_read(fd, buf, size); |
154 | |
155 | /* Try minix */ |
156 | if (minixsb->s_magic == MINIX_SUPER_MAGIC || |
157 | minixsb->s_magic == MINIX_SUPER_MAGIC2) { |
158 | printk(KERN_NOTICE |
159 | "RAMDISK: Minix filesystem found at block %d\n", |
160 | start_block); |
161 | nblocks = minixsb->s_nzones << minixsb->s_log_zone_size; |
162 | goto done; |
163 | } |
164 | |
165 | /* Try ext2 */ |
166 | n = ext2_image_size(buf); |
167 | if (n) { |
168 | printk(KERN_NOTICE |
169 | "RAMDISK: ext2 filesystem found at block %d\n", |
170 | start_block); |
171 | nblocks = n; |
172 | goto done; |
173 | } |
174 | |
175 | printk(KERN_NOTICE |
176 | "RAMDISK: Couldn't find valid RAM disk image starting at %d.\n", |
177 | start_block); |
178 | |
179 | done: |
180 | sys_lseek(fd, start_block * BLOCK_SIZE, 0); |
181 | kfree(buf); |
182 | return nblocks; |
183 | } |
184 | |
185 | int __init rd_load_image(char *from) |
186 | { |
187 | int res = 0; |
188 | int in_fd, out_fd; |
189 | unsigned long rd_blocks, devblocks; |
190 | int nblocks, i, disk; |
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_fd = sys_open("/dev/ram", O_RDWR, 0); |
199 | if (out_fd < 0) |
200 | goto out; |
201 | |
202 | in_fd = sys_open(from, O_RDONLY, 0); |
203 | if (in_fd < 0) |
204 | goto noclose_input; |
205 | |
206 | nblocks = identify_ramdisk_image(in_fd, rd_image_start, &decompressor); |
207 | if (nblocks < 0) |
208 | goto done; |
209 | |
210 | if (nblocks == 0) { |
211 | if (crd_load(in_fd, out_fd, decompressor) == 0) |
212 | goto successful_load; |
213 | goto done; |
214 | } |
215 | |
216 | /* |
217 | * NOTE NOTE: nblocks is not actually blocks but |
218 | * the number of kibibytes of data to load into a ramdisk. |
219 | */ |
220 | if (sys_ioctl(out_fd, BLKGETSIZE, (unsigned long)&rd_blocks) < 0) |
221 | rd_blocks = 0; |
222 | else |
223 | rd_blocks >>= 1; |
224 | |
225 | if (nblocks > rd_blocks) { |
226 | printk("RAMDISK: image too big! (%dKiB/%ldKiB)\n", |
227 | nblocks, rd_blocks); |
228 | goto done; |
229 | } |
230 | |
231 | /* |
232 | * OK, time to copy in the data |
233 | */ |
234 | if (sys_ioctl(in_fd, BLKGETSIZE, (unsigned long)&devblocks) < 0) |
235 | devblocks = 0; |
236 | else |
237 | devblocks >>= 1; |
238 | |
239 | if (strcmp(from, "/initrd.image") == 0) |
240 | devblocks = nblocks; |
241 | |
242 | if (devblocks == 0) { |
243 | printk(KERN_ERR "RAMDISK: could not determine device size\n"); |
244 | goto done; |
245 | } |
246 | |
247 | buf = kmalloc(BLOCK_SIZE, GFP_KERNEL); |
248 | if (!buf) { |
249 | printk(KERN_ERR "RAMDISK: could not allocate buffer\n"); |
250 | goto done; |
251 | } |
252 | |
253 | printk(KERN_NOTICE "RAMDISK: Loading %dKiB [%ld disk%s] into ram disk... ", |
254 | nblocks, ((nblocks-1)/devblocks)+1, nblocks>devblocks ? "s" : ""); |
255 | for (i = 0, disk = 1; i < nblocks; i++) { |
256 | if (i && (i % devblocks == 0)) { |
257 | printk("done disk #%d.\n", disk++); |
258 | rotate = 0; |
259 | if (sys_close(in_fd)) { |
260 | printk("Error closing the disk.\n"); |
261 | goto noclose_input; |
262 | } |
263 | change_floppy("disk #%d", disk); |
264 | in_fd = sys_open(from, O_RDONLY, 0); |
265 | if (in_fd < 0) { |
266 | printk("Error opening disk.\n"); |
267 | goto noclose_input; |
268 | } |
269 | printk("Loading disk #%d... ", disk); |
270 | } |
271 | sys_read(in_fd, buf, BLOCK_SIZE); |
272 | sys_write(out_fd, buf, BLOCK_SIZE); |
273 | #if !defined(CONFIG_S390) |
274 | if (!(i % 16)) { |
275 | pr_cont("%c\b", rotator[rotate & 0x3]); |
276 | rotate++; |
277 | } |
278 | #endif |
279 | } |
280 | printk("done.\n"); |
281 | |
282 | successful_load: |
283 | res = 1; |
284 | done: |
285 | sys_close(in_fd); |
286 | noclose_input: |
287 | sys_close(out_fd); |
288 | out: |
289 | kfree(buf); |
290 | sys_unlink("/dev/ram"); |
291 | return res; |
292 | } |
293 | |
294 | int __init rd_load_disk(int n) |
295 | { |
296 | if (rd_prompt) |
297 | change_floppy("root floppy disk to be loaded into RAM disk"); |
298 | create_dev("/dev/root", ROOT_DEV); |
299 | create_dev("/dev/ram", MKDEV(RAMDISK_MAJOR, n)); |
300 | return rd_load_image("/dev/root"); |
301 | } |
302 | |
303 | static int exit_code; |
304 | static int decompress_error; |
305 | static int crd_infd, crd_outfd; |
306 | |
307 | static long __init compr_fill(void *buf, unsigned long len) |
308 | { |
309 | long r = sys_read(crd_infd, buf, len); |
310 | if (r < 0) |
311 | printk(KERN_ERR "RAMDISK: error while reading compressed data"); |
312 | else if (r == 0) |
313 | printk(KERN_ERR "RAMDISK: EOF while reading compressed data"); |
314 | return r; |
315 | } |
316 | |
317 | static long __init compr_flush(void *window, unsigned long outcnt) |
318 | { |
319 | long written = sys_write(crd_outfd, window, outcnt); |
320 | if (written != outcnt) { |
321 | if (decompress_error == 0) |
322 | printk(KERN_ERR |
323 | "RAMDISK: incomplete write (%ld != %ld)\n", |
324 | written, outcnt); |
325 | decompress_error = 1; |
326 | return -1; |
327 | } |
328 | return outcnt; |
329 | } |
330 | |
331 | static void __init error(char *x) |
332 | { |
333 | printk(KERN_ERR "%s\n", x); |
334 | exit_code = 1; |
335 | decompress_error = 1; |
336 | } |
337 | |
338 | static int __init crd_load(int in_fd, int out_fd, decompress_fn deco) |
339 | { |
340 | int result; |
341 | crd_infd = in_fd; |
342 | crd_outfd = out_fd; |
343 | |
344 | if (!deco) { |
345 | pr_emerg("Invalid ramdisk decompression routine. " |
346 | "Select appropriate config option.\n"); |
347 | panic("Could not decompress initial ramdisk image."); |
348 | } |
349 | |
350 | result = deco(NULL, 0, compr_fill, compr_flush, NULL, NULL, error); |
351 | if (decompress_error) |
352 | result = 1; |
353 | return result; |
354 | } |
355 |